This verse begins with the proposition that the LORD is good. It is a verse primarily about the character of a person—the LORD. It begins with a declaration of his goodness, and concludes with a principle of fact deduced from that character. A principle which relates to truth itself.

So we will consider each point that this verse makes as a logical argument in reference to the truth. The first point it makes is that the LORD is good. But before we can consider the implications of his goodness, we should consider the basic underlying implications of that great name itself. Who is the LORD?

Scripture declares that the LORD is JEHOVAH, the Almighty God. Character traits are not built into the most basic essence of the concept of God, which is why these will be stated explicitly in this verse. But there are some aspects of the divine nature that are implicit in the very concept of the Godhead—namely, infinite power and wisdom. So we need to first consider the implications of these in regard to truth, before we even consider the implications of the LORD’s goodness. What are the implications of the LORD’s Godhead?

Because as God the LORD is infinite in wisdom, we can first deduce that this makes him fully knowledgeable of the truth. And because God is also infinite in power, he is fully capable of revealing truth to mankind.

But ability alone does not imply initiative. Why would God bother to declare truth to man?

The LORD is good #

That is why this verse begins with a declaration of the LORD’s goodness. As a good God, he would not maliciously keep man in the dark, nor lead him into folly. He would declare truth to us, and only truth, and not falsehood.

That is, we would expect a good God to do this to his obedient servants. But mere goodness doesn’t compel one to reveal truth to those who are in sin and rebellion. Thus, the goodness of God, alone, does not guarantee that revelation.

His mercy is everlasting #

But the LORD God is not only good, he is also merciful. This indicates that despite man’s rebellion, the LORD would still declare to us the truth. Nor need we fear that his patience would be soon exhausted, and that we would be left without the light. For his mercy is everlasting.

His truth endureth to all generations #

To what other conclusion can one come? His truth endures to all generations. His Godhead gives him the ability. His goodness gives him the will. And his mercy gives him everlasting perseverance. He can declare his truth. He will declare his truth. And he will preserve his truth—so that it endures to all generations.

What is truth? #

And where is that truth? According to Christ, God’s truth is in his word:

John 17:17 Sanctify them through thy truth: thy word is truth.

Thus, since God’s truth endures, his word must endure unto all generations.

But do we believe it? #

Yet there are many which do not believe this. But what part of Psalm 100:5, exactly, do they not believe?

Is it that they do not believe that the LORD is God? Do they doubt his power or his wisdom? Do they think him unable to declare or to preserve his word?

Or do they not believe that the LORD is good, suspecting him of maliciousness, or doubting whether he would care to give truth to mere men?

Or do they believe that the good LORD God has given truth to man, but that he is not merciful enough to preserve it? Do they doubt the eternal endurance of his mercy, and thus of his truth?

But to doubt that God’s mercy is everlasting, is to doubt the everlasting nature of his salvation, which is predicated on that mercy.

So again we must ask, of our brethren who doubt preservation: what part of this verse is it that you do not believe?

As for us, we believe it wholly. We serve a LORD God that is not only infinitely wise and powerful, but also supremely good, and everlastingly merciful. Who has given, and promised to preserve, his word. And we can trust that what he has promised, he is able to—and will—perform.