John Calvin Commentary Psalms 132:18

"His enemies will I clothe with shame; But upon himself shall his crown flourish." — Psalms 132:18 (ASV)

His enemies will I clothe with shame. The priests were said above “to be clothed with righteousness and salvation;” now the enemies of David are represented as “clothed with shame.” It is not enough that all goes well within. God must keep us from the various harms and evils that come upon us from outside, and therefore we have this second promise added, which is one in which we often recognize the goodness of God even more than in the blessings He may shower upon us in the day of prosperity.

The greater the fear that seizes us when exposed to aggression from enemies, the more we are perceptibly awakened to take hold of divine help. The passage teaches us that the Church and people of God will never enjoy such peace on earth as to escape entirely being assaulted by the variety of enemies whom Satan stirs up for their destruction.

It is enough to have it declared, upon divine authority, that their attempts will be unsuccessful, and that they will eventually retire with ignominy and disgrace. The clause that follows has been variously interpreted. The verb that we have translated to flourish, in the Hiphil conjugation, sometimes means to see, so that some have explained the words: “In that place the crown of David will be seen, when the horn has been made to bud.” Some derive the word from ציף, tsits, a plate, as if it had been said that the crown of the king would be resplendent with plates of gold. But I consider that the crown is here said to flourish, just as formerly the allusion was to budding or germinating. Isaiah, on the other hand, speaks (Isaiah 28:5) of the crown of drunkenness of Ephraim as being a fading flower. Thus we have it here declared that however frail in appearance the crown of David might be in his posterity, it would be invigorated by some secret virtue and flourish forever.