John Calvin Commentary Psalms 76:12

"He will cut off the spirit of princes: He is terrible to the kings of the earth." — Psalms 76:12 (ASV)

He will cut off the spirit of princes. As the Hebrew word בצר, batsar, occasionally signifies to strengthen, some think it should be translated as such in this passage. But since the same sentiment is repeated in the two clauses of the verse, I have no doubt that the first clause means that understanding and wisdom are taken away from princes; and that by the second, God is represented in general as terrible to them, because He will cast them down headlong from their loftiness.

Since sound foresight is the first thing necessary to bring an enterprise to a successful conclusion—a quality in which God's people are often deficient due to the great perplexity of their distresses, while, on the other hand, the ungodly are too sharp-sighted in their crafty schemes—it is declared here that God has the power to deprive of understanding and to inflict blindness on those who seem to surpass others in acuteness and ingenuity.

Since the majority of princes are enemies to the Church of God, it is expressly affirmed that He is sufficiently terrible to subdue all the kings of the earth. When it is said, their spirit is cut off, or taken away from them, this applies specifically to tyrants and robbers whom God confounds, because He sees that they apply all their ingenuity and plans to do evil.