Rashi on the Prophets and Writings
Psalms 52
on machalath The name of a musical instrument. Another explanation: concerning the malady (מחלתן) of Israel when the Temple will be destroyed. He already recited another psalm resembling this one (above 14): “The fool said in his heart, ‘there is no God, etc.’ “, One relates to the destruction of the First Temple and this one, to the Second Temple.
The fool said in his heart This is Titus; when he cut into the curtain and his sword was dripping with blood, he said that he had killed [God] Himself.
dross Heb. סג, an expression of סיגים, dross. not even one of all his armies will protest against his deeds.
Did not Should not those who devour My people like a meal of bread, and who did not call upon the Lord, know that ultimately they will experience there a great fear at the end of days?
there was never such fear This fear was not like the first fear that came over Belshazzar, for in this redemption the Holy One, blessed be He, scattered the bones of חוֹנָךְ, those who camp around you, Jerusalem, as the matter that is stated (Zech. 14:12): “His flesh will waste away, etc.” Menachem (p. 91) interpreted it that way, but Dunash (pp. 63f.) interpreted it as (Prov. 22:6): “Train (חנך) a child according to his way”; the “chaph” of חוֹנָךְ is a radical as the “chaph” of חֲנֹךְ, train. You have put them to shame You, O Lord, have put all my enemies to shame, for You have rejected them.
You arrive at the cited line; the whole work is yours to read around it. The text is set from the cited public-domain edition.