Verse 6
But I am appointed king by him over Sion his holy mountain, preaching his commandment.
Ego autem constitutus sum rex ab eo super Sion, montem sanctum ejus, praedicans praeceptum ejus.
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Let us now come to the meaning. The prophet had said theat Christ’s enemies would be in an uproar, and he uttered the following words: “Let us break their bonds asunder” etc. Now he introduces Christ himself speaking and responding to them, as though to say: the nations and peoples, indeed the kings and the princes say: “Let us break their bonds asunder; truly, God shall laugh at them and Christ Himself shall respond to them : I am ordained King not by men but by God, and therefore I do not fear the threats of men; I am ordained King over Sion, His holy mountain, that is, over the Church, which is a city built on a mountain, of which Jerusalem was a type, the chief part of which, and the most beloved and sanctified of God, was Sion, as Psalm LXXXVI says: The Lord loveth the gates of Sion above all the tabernacles of Jacob.