תהילים ז:יב פירוש: רש״י ורד״ק

a righteous judge are You to judge with righteousness.

God is a righteous Judge: – as (in the verse) Judge me, O Lord, according to my righteousness (supra, 5:9); and its interpretation (is): God judges the righteous according to his righteousness and the wicked according to his wickedness, and this is what he means when he says:

is incensed every day when He sees the deed of the wicked.