John Calvin Commentary Luke 1:17

"And he shall go before his face in the spirit and power of Elijah, to turn the hearts of the fathers to the children, and the disobedient [to walk] in the wisdom of the just; to make ready for the Lord a people prepared [for him]." — Luke 1:17 (ASV)

And he shall go before him. By these words, the angel points out what John’s office would be and distinguishes him by this characteristic from the other prophets, who received a specific and unique commission, while John was sent for the sole purpose of going before Christ, as a herald before a king. The Lord also speaks this way through Malachi,

“Behold, I will send my messenger, and he shall prepare the way before me,”
(Malachi 3:1).

In short, John’s calling had no other purpose than to secure a willing ear for Christ and to prepare disciples for Him. Regarding the angel making no explicit mention of Christ in this passage, but declaring John to be the usher or standard-bearer of the eternal God, we learn from this the eternal divinity of Christ.

With the spirit and power of Elijah. By the words spirit and power, I understand the power or excellence of the Spirit with which Elijah was endowed. We must not indulge here in a dream like that of Pythagoras, that the prophet's soul passed into John's body. Instead, the same Spirit of God, who had acted effectively in Elijah, afterward exerted a similar power and effectiveness in the Baptist.

The latter term, power, is added explanatorily to denote the kind of grace that was Elijah’s highest distinction: that, equipped with heavenly power, he wonderfully restored the decayed worship of God, for such a restoration was beyond human capability. What John undertook was no less astonishing; therefore, we should not wonder that it was necessary for him to enjoy the same gift.

That he may bring back the hearts of the fathers. Here the angel points out the primary resemblance between John and Elijah. He declares that John was sent to gather the scattered people into the unity of faith. For to bring back the hearts of the fathers is to restore them from discord to reconciliation, from which it follows that there had been some division that rent and tore apart the people.

We know how dreadful the people's revolt was in Elijah's time, how basely they had degenerated from their fathers, so that they hardly deserved to be considered Abraham's children. Elijah brought those who were thus divided into holy harmony. Such was the reunion of parents with children, which was begun by John and ultimately finished by Christ.

Accordingly, when Malachi speaks of “turning the hearts of the fathers to the children” (Malachi 4:5), he suggests that the Church would be in a state of confusion when another Elijah should appear. What that state was is clear enough from history and will appear more fully in its proper place. The doctrine of Scripture had degenerated through countless human inventions, the worship of God was corrupted by very crude superstition, religion was divided into various sects, priests were openly wicked and Epicureans, and the people indulged in every kind of wickedness; in short, nothing sound remained.

The expression, bring back the hearts of the fathers to the children, is not literally true, for it was rather the children who had broken the covenant and departed from the right faith of their fathers who needed to be brought back. But though the Evangelist does not express that order of bringing back so literally, the meaning is abundantly obvious: that, by the agency of John, God would again unite in holy harmony those who had previously been divided. Both clauses occur in the prophet Malachi, who meant nothing more than to express a mutual agreement.

But as men frequently enter into mutual conspiracies that drive them further from God, the angel explains, at the same time, the nature of that bringing back which he predicts: the disobedient to the wisdom of the just. This deserves attention, so that we do not foolishly allow ourselves to be grouped with ungodly men under a false pretext of harmony.

Peace is a grand and imposing term, and whenever the Papists encounter it in Scripture, they eagerly seize upon it for the purpose of stirring up dislike against us, as if we, who are striving to withdraw the world from its vile revolt and bring it back to Christ, were the originators of divisions. But this passage affords a clear exposure of their folly, when the angel explains the nature of a genuine and proper conversion and declares its support and link to be the wisdom of the just. Then accursed be the peace and unity by which men agree among themselves apart from God.

By the wisdom of the just unquestionably means Faith, as, conversely, by the disobedient are meant Unbelievers. And certainly, this is remarkable praise for faith, by which we are taught that only then are we truly wise in righteousness when we obey the Lord's word.

The world also has its wisdom, but it is a perverse and therefore destructive wisdom, which is always declared to be vanity; although the angel indirectly asserts that the shadowy wisdom in which the children of the world delight is depraved and accursed before God. This is, therefore, a settled point: to become reconciled to each other, men must first return to peace with God.

What immediately follows about making ready a people prepared for the Lord, aligns with the previously quoted clause from Malachi 3:1, indicating that John, as Christ’s herald, would go before His face. For the purpose of his preaching was to make the people attentive to Christ's instruction. The Greek participle κατεσκευασμένον, indeed, does not exactly mean perfection as much as the form and adaptation by which things are fitted for their use. This meaning fits well with the present passage. John was commissioned to fit or mold for Christ a people who, formerly ignorant and uneducated, had never shown a desire to learn.