Thomas Aquinas Commentary 1 Thessalonians 5

In what he had written before, Paul corrected the Thessalonians in matters that needed improvement, and now he begins to instruct them about the future. He first gives them a warning and then provides a prayer with the words, "may the God of peace himself sanctify you wholly." These two things are indeed necessary for us. Because the good deeds we do are a result of free will, a person can profit from a warning. And since these deeds are also a result of grace, a person needs prayer as well.

Concerning the first point, he does two things: Paul first urges the Thessalonians to prepare themselves for the coming judgment; second, he shows them how they should prepare themselves (1 Thessalonians 5:11). He also divides the first part into two: he points out a feature of the coming judgment and then shows how they ought to prepare for it (1 Thessalonians 5:6). There is also a subdivision of the first section into two further parts that include this feature of the coming judgment and then an explanation (1 Thessalonians 5:3). In the first part, Paul puts to rest their concern for knowledge about the future coming, and then he addresses what they did know about it (1 Thessalonians 5:2).

First, then, Paul says it was necessary for me to write about the previous matters because you needed to know about them. But concerning the times and seasons of what the future will be, it was not necessary to write. This is because some of these things are reserved for God's knowledge alone: “But concerning that day or that hour, no one knows, not even the angels in heaven, nor the Son, but only the Father” (Mark 13:32). “It is not for you to know times or seasons that the Father has fixed by his own authority” (Acts 1:7). “The more words, the more vanity, and what is man the better? For who can tell a man what is good for him in this life, the few days of his vain life, which he passes like a shadow?” (Ecclesiastes 6:11–12). Therefore, it is not necessary to write about this, for you yourselves know what needs to be known: that the day of the Lord will come like a thief in the night.

In fact, all days depend on the Lord: “By your appointment they stand this day” (Psalms 119:91). But this day especially belongs to the Lord, because His will is fulfilled in everyone. It is accomplished in the good, who are led to salvation as an end foreknown by God: “who desires all men to be saved and to come to the knowledge of the truth” (1 Timothy 2:4); and in the wicked who are punished: “At the set time which I appoint I will judge with equity” (Psalms 75:2).

It will come like a thief—that is, unannounced: “If the master of the house had known at what hour the thief was coming, he would have been awake” (Luke 12:39). “The day of the Lord will come like a thief” (2 Peter 3:10). “I will come like a thief” (Revelation 3:3). But why is it said that the day will come during the night? It should be understood that both are involved. He comes during the day to uncover our hearts: “before the Lord comes, who will bring to light the things now hidden in darkness and will disclose the purposes of the heart” (1 Corinthians 4:5). But He comes at night because of the element of surprise: “Behold, the bridegroom! Come out to meet him” (Matthew 25:6). In truth, it is not certain at what hour it will occur.

Then when he says, “While people are saying, ‘There is peace and security,’” he explains what he had mentioned. First, he refers to the wicked; second, to the good (1 Thessalonians 5:4). In regard to the first division, he does two things. He first describes the false confidence of the wicked and second, he refers to the danger of a delay. So Paul says the Lord will come like a thief because He will come unexpectedly. When people say, “There is peace,” they will be deceived regarding the present time when they are living tranquilly: “But they live in great strife due to ignorance, and they call such great evils peace” . “Security” refers to the future: “Soul, you have ample goods laid up for many years; relax, eat, drink, be merry” (Luke 12:19).

In contrast to this: “people fainting with fear and with foreboding of what is coming on the world” (Luke 21:26). Thus, there is no security to be had. There are two explanations for this. The one offered by Augustine is that at that time some will be good, but they will be afflicted, mourning, and waiting expectantly; this is referred to in the quotation as “fainting” because of the absence of pleasures and the abundance of evils. But there will be peace and security among the wicked. The other explanation is found in the Gloss.

Then when he says, “then sudden destruction will come upon them,” he presents four aspects of the peril. First, that it will be unexpected, where he says, sudden, “like a breach in a high wall... whose crash comes suddenly, in an instant” (Isaiah 30:13). Second, he describes the peril as deadly when he says destruction. “Destruction will tread upon him as a king” (Job 18:14). Third, he refers to the peril as distressing, and he uses the word travail: “Anguish as of a woman in travail” (Psalms 48:6). Fourth, he presents the peril as inevitable when he comments, “and they will not escape.” Now is the time to escape from the wrath of God to the mercy of God, for the end of the world will not be a time of mercy but of justice.

Then Paul says, “But you are not in darkness, brothers,” and explains what he had mentioned regarding the good. He does this by making two points: first, he excludes the good from the company of the wicked, and second, he provides a reason for this (1 Thessalonians 5:5). And so he remarks, you are not in darkness, for you have been enlightened by Christ concerning that day; this is not an unexpected event for you. “He who follows me will not walk in darkness, but will have the light of life” (John 8:12). The reason for this is given in the words, “for you are all sons of light.” He also makes the point that they are sons of the light and of the day. According to the Scriptures, someone is said to be the “son” of something because he abounds in it. “My beloved had a vineyard on a very fertile hill”—literally, a “son of oil”—(Isaiah 5:1), meaning it was very rich land. Those who participate greatly in the day and in the light are called their sons. And this light is the faith of Christ. “I am the light of the world” (John 8:12), and again, “Believe in the light, that you may become sons of light” (John 12:36).

He adds, “and sons of the day,” for just as the early light leads to the fullness of the day, so the faith of Christ leads to the day that is the brilliance of good actions. “The night is far gone, the day is at hand” (Romans 13:12). And because of this, you are not of the night—that is, involved in unbelief—or of darkness, that is, of sin. “Let us then cast off the works of darkness and put on the armor of light” (Romans 13:12).

Then when he says, “So then, let us not sleep,” he shows them how they should prepare for that coming. First, they should prepare for it by staying away from evil; second, they should prepare by regularly doing good (1 Thessalonians 5:8).

In making the first point, he does two things. First, he gives a warning, and then he sets down the reason for it (1 Thessalonians 5:7). Paul says, therefore, that the day of the Lord is like a thief for this reason: “If the master of the house had known at what hour the thief was coming, he would have been awake” (Luke 12:39). And so you know you must be vigilant. He adds, “so then let us not sleep,” in the sleep of sin: “Awake, O sleeper, and arise from the dead” (Ephesians 5:14). “How long will you lie there, O sluggard? When will you arise from your sleep?” (Proverbs 6:9).

But let us stay awake and be vigilant. “Watch therefore, for you do not know on what day your Lord is coming” (Matthew 24:42). To this end, it is necessary that we be sober, so that both body and mind are sober—that is, free from the pleasures and cares of the world. “But take heed to yourselves lest your hearts be weighed down with dissipation and drunkenness” (Luke 21:34). “Be sober-minded; be watchful” (1 Peter 5:8). The reason for this relates to the proper time for such activities; those who sleep or get drunk do so at night. But the night is not for us, so then, “let us not sleep, as others do.” And so Paul says, “For those who sleep, sleep at night,” that is, at night they get some rest and during the day they are active. “When the sun rises, they steal away and lie down in their dens” (Psalms 104:22). And again, “Man goes out to his work and to his labor until the evening” (Psalms 104:23).

There are also some who do not drink during the day because of business that must be done, but they are not so careful at night. “The eye of the adulterer also waits for the twilight” (Job 24:15). So sleep and drunkenness are fitting for the night, since the sinful are occupied with sin during the night of unbelief and the darkness of evil, having no regard for the future because of their love for present concerns. “They have become callous and have given themselves up to licentiousness, greedy to practice every kind of uncleanness” (Ephesians 4:19). But since we belong to the day—that is, the daytime of integrity and faith—let us be sober. “Let us walk properly as in the daytime” (Romans 13:13).

When Paul says, “let us put on the breastplate of faith,” he shows how they should prepare themselves through good actions. First, he sets down a general exhortation, and then he issues a special one (1 Thessalonians 5:11). He divides the first point into two aspects: he first gives the exhortation itself and then gives the reason for it (1 Thessalonians 5:9). In a person, there are two vital parts of the body that were protected in war: the heart, the source of life, and the head, which governs the body’s movements and is the seat of the senses. The heart is protected by a breastplate and the head by a helmet. The life of the spirit in us is Christ, through whom the soul lives and the Lord dwells in us: “that Christ may dwell in your hearts through faith—that you, being rooted and grounded in love...” (Ephesians 3:17). “He who abides in love abides in God, and God abides in him” (1 John 4:16). Love gives life to faith. Therefore, we must have faith and love, and so Paul calls for “the breastplate of faith and love,” because it protects the body’s vital parts, and for a helmet, “the hope of salvation,” because salvation is a spiritual motivation, as it is the goal we hope to attain.

When he says, “For God has not destined us for wrath,” he shows the way God works in us. This is shown first through divine preordination and then as derived from the grace of Christ. Finally, Paul discusses the way salvation is to be achieved. He begins with the words, “God has not destined us,” that is, God has not appointed us: “I appointed you that you should go and bear fruit” (John 15:16); “for wrath,” that is, that we should deserve His wrath: “God did not make death” . “Have I any pleasure in the death of the wicked, says the Lord God, and not rather that he should turn from his way and live?” (Ezekiel 18:23). But “to obtain salvation,” that is, so that we might acquire salvation, “from the days of John the Baptist until now the kingdom of heaven has suffered violence, and the violent take it by force” (Matthew 11:12). “But you are a chosen race, a royal priesthood, a holy nation, a people for his own possession” (1 Peter 2:9). This is achieved through Christ’s grace; hence he says, “through our Lord Jesus Christ.” “For there is no other name under heaven given among men by which we must be saved” (Acts 4:12).

“Who died for us” means that He redeemed us by dying for us. “The righteous died for the unrighteous, that he might bring us to God, being put to death in the flesh but made alive in the spirit” (1 Peter 3:18). The way of attaining salvation is also through Him, for Christ taught us this while working for our salvation, which He achieved by dying and rising again. “Who was delivered up for our trespasses and raised for our justification” (Romans 4:25). And so Paul says, “so that whether we are awake or asleep we might live with him.” “So then, whether we live or whether we die, we are the Lord's” (Romans 14:8).

When he says, “Therefore encourage one another,” he teaches us how we should behave toward different groups of people. First, he shows how they should behave toward their peers; second, how they should be subject to their leaders (1 Thessalonians 5:12); and finally, how the leaders should behave toward their flock (1 Thessalonians 5:14).

To our peers, we owe comfort in times of difficulty, and so he says, “encourage one another.” In addition, we should inspire them by example, and so he says, “and build one another up.” “Let us then pursue what makes for peace and for mutual upbuilding” (Romans 14:19).

Those who are under the authority of leaders owe them, first, acknowledgment of their work; second, love; and third, peace. “Respect those who labor among you” means to acknowledge their work: “Remember your leaders, those who spoke to you the word of God” (Hebrews 13:7). I say that you should respect them, first, for their own sake, because of the great labors they have undertaken for you. And so he mentions “those who labor among you” for your good. “Share in suffering as a good soldier of Christ Jesus” (2 Timothy 2:3). Second, you should respect them on God's behalf; because of this, reverence is due to them as it is due to God. And so Paul remarks, “and are over you in the Lord,” that is, in the place of God. “If I have forgiven anything, it has been for your sake in the presence of Christ” (2 Corinthians 2:10). Third, you should respect them for your own sake, because they are helpful to you; hence he says, “and admonish you.” Furthermore, you owe them love; hence, “esteem them very highly in love,” that is, above others.

Finally, “be at peace with them” because of their work. Yet some people act against this. “They hate him who reproves in the gate, and they abhor him who speaks the truth” (Amos 5:10). “One who rejoices in wickedness will be condemned” . Nevertheless, you should be at peace with them because of their work of correction, for this work properly belongs to their office. “I am for peace, but when I speak, they are for war!” (Psalms 120:7).

Earlier, he showed them how they should remain subject to their bishops. Here he makes the same point from another point of view. Regarding this, he does two things: first, he teaches how bishops should act toward their priests, and second, he teaches them in general how they should behave toward everyone (1 Thessalonians 5:15).

It should be understood that the concern of bishops should be directed toward two things: to prevent others from sinning and to safeguard themselves in this respect.

In addressing the first point, Paul does three things, corresponding to the three ways those under authority may fail: in action, in will, and in virtue.

They fail in action when they give themselves over to sin, and then they should be corrected. Although they should be corrected for every sin, they should be corrected especially for the sin of idleness, and so Paul remarks, admonish the idle. “We were not idle when we were with you” (2 Thessalonians 3:7). “Question your neighbor before you threaten him” .

Their will may be at fault if they undertake no great tasks, being despondent because of their adversities and past sins. Consequently, Paul says, encourage the fainthearted. A person is considered fainthearted if he lacks the courage for great things because he is afraid of failing. “Say to those who are of a fearful heart, Be strong, fear not!” (Isaiah 35:4). “Your words have upheld him who was stumbling” (Job 4:4).

They fail in virtue when they sin from weakness or are halfhearted in a good act, and these people need to be supported. So Paul remarks, help the weak—that is, assist them with all charity, for their own power is weak for resisting evil or for doing good works. “We who are strong ought to bear with the failings of the weak” (Romans 15:1).

A bishop should guard himself against any kind of fault, and especially against impatience, for he is bearing the full burden of the group. “I am not able to carry all this people alone, the burden is too heavy for me” (Numbers 11:14). Therefore, he says, be patient with them all. “Good sense makes a man slow to anger” (Proverbs 19:11).

Then, when Paul says, see that none of you repays evil for evil, he shows them in general how they should behave toward everyone. Regarding this, he does two things: first, he shows how everyone should behave in certain matters; second, he shows how they should behave in all things (1 Thessalonians 5:21).

In regard to the first, he makes three points, showing how they should behave: first, toward their fellow men; second, in matters that pertain to God (1 Thessalonians 5:16); and third, with respect to His gifts (1 Thessalonians 5:19).

First, they should not be malicious toward their fellow men but should try to be kind to them. Whereas Paul spoke in particular before, now he speaks in general: see that none of you repays evil for evil. “If I have repaid my friend with evil, let the enemy pursue me...” (Psalms 7:4).

On the other hand, retribution is frequently sought before a judge. It should be pointed out that a moral act is defined by its intended end. The intention, however, can be of two kinds. One may desire the mere misfortune of another, and this is wrong because of its vengeful character. Alternatively, the act may be aimed at the good of correction, or at justice and the protection of the public interest.

In this latter case, one does not repay evil for evil but rather good, which is the corrective for evil.

Regarding the second point, Paul says, always seek to do good. He says “seek” and not “do,” because you must seek the opportunity to do good for your neighbor, not wait for your neighbor to provide you with one. “Seek peace, and pursue it” (Psalms 34:14). Paul also says, “Do not be overcome by evil”—that is, do not be attracted by it to do wrong—“but overcome evil with good” (Romans 12:21). “As we have opportunity, let us do good to all men” (Galatians 6:10).

Second, regarding matters that pertain to God, when Paul says, rejoice always, he shows how they should behave toward God. He mentions three things.

First, they are to rejoice in Him. Paul says, rejoice always—that is, in God. For whatever evil might occur, it is incomparable to the goodness that is God. Therefore, no evil should interrupt this joy, and so Paul insists, rejoice always.

Second, they are to pray for the blessings they want to receive. Paul urges, pray constantly. “They ought always to pray and not lose heart” (Luke 18:1).

How is this possible? It may happen in three ways:

1. The person who does not neglect the appointed hours for prayer is said to pray always. “You shall eat at my table always” (2 Samuel 9:7).
2. To “pray constantly” can mean to pray continuously in effect. Here, prayer is considered in terms of its effect. Prayer is the expression of desire; when I desire something, I ask for it by praying. Thus, prayer is the petition for suitable things from God, and so desire has the power of prayer. “O Lord, you will hear the desire of the meek” (Psalms 10:17). Since whatever we do is the result of a desire, prayer remains in force in the good things we do, for our good works flow from the desire for good. A commentary on this verse points out: “He does not cease praying who does not cease doing good.”
3. A third way to pray without ceasing is by giving alms, which can be a cause of continual prayer. In the lives of the Fathers we read: “He who gives alms is the one who always prays, for the person who receives alms prays for you even when you are asleep.”

Third, they are to offer thanks for blessings already received. Hence, Paul says, in all circumstances... give thanks—that is, in good times and bad. “We know that in everything God works for good with those who love him” (Romans 8:28). “Abounding in thanksgiving” (Colossians 2:7). “With thanksgiving” (Philippians 4:6). For this is the will of God in Christ Jesus for you. “Who desires all men to be saved and to come to the knowledge of the truth” (1 Timothy 2:4).

Third, regarding God's gifts, when Paul says, do not quench the Spirit, he shows them how to regard them. He shows first that they must not diminish the Spirit's gifts, and second, that they must not despise them (1 Thessalonians 5:20).

The Holy Spirit is a divine, incorruptible, and eternal person, so He cannot be extinguished in His own substance. Nevertheless, someone is said to quench the Spirit in three ways:

1. By extinguishing the fervor of the Spirit, either in oneself or in someone else. “Be aglow with the Spirit” (Romans 12:11). When someone wishes to do something generous from the impulse of the Holy Spirit, or even when a generous inclination arises, and that person hinders it, he extinguishes the Holy Spirit. “You always resist the Holy Spirit” (Acts 7:51).
2. By mortal sin. The Holy Spirit always abides in Himself, but He abides in us when He causes us to abide in Him. When someone commits a mortal sin, the Holy Spirit no longer abides in him. “For a holy and disciplined spirit will flee from deceit, and will rise and depart from foolish thoughts, and will be ashamed at the approach of unrighteousness” .
3. By concealing the Spirit's gift. This implies that if you have a gift of the Spirit, you should use it for the benefit of your neighbors. “Hidden wisdom and unseen treasure, what advantage is there in either of them?” . “Nor do men light a lamp and put it under a bushel, but on a stand, and it gives light to all in the house” (Matthew 5:15).

Next, Paul says, Do not despise prophesying. Some among them were gifted with prophecies but were considered insane by others. “Earnestly desire the spiritual gifts, especially that you may prophesy” (1 Corinthians 14:1). Alternatively, prophesying can be understood as divine doctrine, for those who explain divine doctrine are called prophets. In this case, the command means not to despise the words of God and His preachers. “For the word of the Lord has become for me a reproach and derision all day long” (Jeremiah 20:8).

Then, when he says, but test everything, he shows how they should behave toward all things. His advice is that they should use discretion in all matters. “Your spiritual worship” [“Your reasonable service”] (Romans 12:1). This involves a careful examination, the choosing of the good, and the rejection of the evil.

Paul elaborates on these three points. First, regarding examination, he says that while they should not despise prophesying, they must nevertheless test everything that is doubtful, for things that are evident do not require examination. “Do not believe every spirit” (1 John 4:1). “Does not the ear try words?” (Job 12:11). Second, concerning choosing the good, he says, hold fast what is good. “For a good purpose it is always good to be made much of” (Galatians 4:18). Third, regarding evil, Paul says, abstain from every form of evil. “He knows how to refuse the evil and choose the good” (Isaiah 7:15). He says every form because we are obliged to avoid even those actions that only have the appearance of evil—that is, actions we cannot perform in the sight of others without causing scandal.

Then, when Paul says, may the God of peace himself sanctify you wholly, he inserts a prayer. In this section, he does three things: first, he prays on their behalf; second, he indicates that his prayer will be heard; and finally, he issues special admonitions. Paul implies, “I have given my advice, but remember that nothing will come of it unless God gives you grace.” Therefore, he prays, may the God of peace himself sanctify you. “I am the Lord who sanctify you” (Leviticus 22:32). He prays that they be sanctified wholly, so that they may be completely holy, and may your spirit and soul and body be kept sound.

Because of these words, some have maintained that the spirit in man is one element and the soul another, thus proposing two souls in man: one that animates the body and another that performs the function of reasoning. These opinions are rejected in the Church’s teaching.

It should be understood that these two elements, which are really one, do not differ essentially, but only because of the powers present in them. There are certain powers in our soul linked to bodily organs, such as the powers of the sensitive part of the soul. There are other powers not linked to bodily organs, which function apart from the body; these are the powers of the intellectual part of the soul. These latter powers are regarded as spiritual because they are immaterial and, in a way, separate from the body, as they are not functions of the body but are referred to as the mind. “Be renewed in the spirit of your minds” (Ephesians 4:23). Yet it is called the soul in that it animates the body, for this is its proper function. Paul speaks here in a specific sense.

There are three elements involved in sin: reason, the sensitive appetite, and the actions of the body. Paul is anxious that all three of these areas be free from sin. Because he wants reason to be free from sin, he says, may your spirit—that is, your mind—be kept sound. For in every sin, reason is corrupted in the sense that every evil person is in some way ignorant. There should be no sin in the sensitive appetite either, to which Paul refers when he says, and soul. Nor should there be sin in the body, so Paul adds, and body. This is achieved when the body is preserved immune from sin.

Paul also says, and blameless. This is different from being “without sin,” which can be attributed only to Christ. To be “blameless” can also be said of those who, although they may commit venial sins, have not committed grave sins by which others may be scandalized. “Walking in all the commandments and ordinances of the Lord blameless” (Luke 1:6). Paul adds, at the coming of our Lord Jesus Christ, which means persevering until the end of life. Alternatively, the word “spirit” may refer to the gift of the Holy Spirit, as if implying, “May the gift of the Holy Spirit that you have remain unimpaired.”

Then, when Paul says, He who calls you is faithful, he expresses the hope that his prayer will be heard. It is as if he is saying, “It will come about as I hope, for He who calls you will do it”—that is, He will accomplish it. “The Lord is faithful in all his words” (Psalms 145:13). “And those whom he called he also justified” (Romans 8:30).

Finally, Paul adds some familiar admonitions. He urges prayer and mutual peace: greet all the brethren with a holy kiss. This should not be a treacherous kiss like that of Judas (Matthew 26), nor a passionate kiss like that of the lustful woman in Proverbs (Proverbs 7:13).

I adjure you by the Lord that this letter be read to all the brethren. Paul feared that those in charge of the assembly might suppress it because of some of the things it contained. “The people curse him who holds back grain, but a blessing is on the head of him who sells it” (Proverbs 11:26).

Finally, he concludes the letter with a greeting.