Albert Barnes Commentary Psalms 100:5

"For Jehovah is good; his lovingkindness [endureth] for ever, And his faithfulness unto all generations." — Psalms 100:5 (ASV)

For the Lord is good. For good is Yahweh. That is, He is not a being of mere "power"; He is not merely the Creator; but He is benevolent and is, therefore, worthy of universal praise. In the former verses, His claim to adoration is founded on the fact that He is the "Creator," and has, as such, a right to our service; in this verse, the claim is asserted on account of His moral character:

1. His benevolence;
2. His mercy;
3. His truth:
   • The fact that He is a God of truth; and
   • The fact that His truth endures, or that in all generations He shows Himself to be faithful to His promises.

The first of these is His "benevolence": The Lord is good. As such, assuredly, God is worthy of praise and honor. A being of "mere" power we could not love or praise; a being whose power was united with malignity or malevolence could only be the object of hatred and terror. But a being whose power is united with goodness or benevolence ought to be loved.

His mercy is everlasting. This is the "second" reason, drawn from His moral character, why He should be praised and adored. A being of mere "justice" may be feared and respected, but a character of "mere" justice would be an object of dread to man—and may be so anywhere.

There are other attributes besides "justice"—high and valuable as that may be—which are necessary to constitute a perfect character. Man, in order to find happiness and security, must find some other attribute in God than mere "justice," for man is a sinner and needs pardon; he is a sufferer and needs compassion; he is to die and needs support and consolation.

Besides, mere "justice" may drive its decisions over some of the kindest and tenderest feelings of human nature, for there are cases, under all administrations, where pardon is desirable and mercy is proper. It is, therefore, a ground of unspeakable joy for man that God is not a Being of "mere justice," but that mercy and kindness are also mingled in His character.

Without this, man could have no hope, for, as a sinner, he has no claim on God, and all his hope must be derived from God’s infinite compassion.

To all this as a ground of praise is to be added the fact that this mercy of God is everlasting. Its fruits—its results—will extend to the vast eternity before us. In all that eternity, we shall never cease to enjoy the benefits of that mercy, never be allowed to fall back on the mere "justice" of God.

And His truth endures to all generations. Margin, as in Hebrew, "to generation and generation." That is, forever. It is the same in every generation of the world. This is the third reason derived from the moral character of God for praising Him, and this is a just ground of praise.

We could not love and honor a God who was not true to His promises and who did not Himself love the truth; we could not honor one who was changeable and flexible—who loved one thing in one generation and a different thing in the next, who in one age was the friend of truth and in the next the patron of falsehood. It is the just foundation for praise to God—our God—that He is essentially and always—in all worlds, and in all the generations of people, toward all in the universe—a Being of unchangeable benevolence, mercy, and truth. Such a God is worthy of universal reverence; such a God is worthy of universal praise.