John Calvin Commentary Psalms 34:21

"Evil shall slay the wicked; And they that hate the righteous shall be condemned." — Psalms 34:21 (ASV)

But malice shall slay the wicked. The Hebrew word רעה, raäh, which I have translated malice, some would rather render misery, so that the meaning would be that the ungodly will perish miserably, because in the end they will be overwhelmed with calamities. The other translation, however, is more expressive: namely, that their wickedness, with which they think themselves fortified, will fall upon their own heads.

Therefore, as David previously taught that there was no better defense than a just and blameless life, so now he declares that all the wicked enterprises of the wicked, even if no one opposes them at all, will turn to their own destruction. In the second clause of the verse, he states that it is for the sake of the righteous that it is ordered that the ungodly are themselves the cause and instruments of their own destruction.

Those, he says, who hate the righteous shall be destroyed. Therefore, let this be to us as a wall of brass and a sure defense; for however numerous the enemies who beset us may be, we should not be afraid, because they are already devoted to destruction.

David confirms the same thing in the last verse, where he says that Jehovah redeems the soul of his servants. How could they be preserved in safety, even for a moment, among so many dangers, unless God interposed his power for their defense?

But the word redeem expresses a kind of preservation that is repugnant to the flesh. For it is necessary that we should first be adjudged or doomed to death before God appears as our redeemer.

From this it follows that those who rush forward too precipitately, and are unable to realize God’s power unless he appears speedily, working deliverance for them, obstruct the flow of his grace.

Moreover, so that no one might form their judgment of God’s servants based solely on what is called moral or philosophic virtue, David specifies this as a principal mark by which they may be known: they trust in God, on whom their salvation also depends.