Romans 3:5

Commend. Gr. sunistemi. This word and its related forms are used in the NT with two shades of meaning: (1) “to commend” (2 Cor. 12:11), and (2) “to establish,” “to prove” (Rom. 5:8; Gal. 2:18, translated “make”). The latter sense probably applies in this passage. Paul is preparing to meet the objection that if the sin of man tends only to commend and establish the righteousness of God, why should that sin be punished?

Righteousness of God. See on ch. 1:17. In this context it would seem that Paul is emphasizing primarily the perfection of the divine character.

What shall we say? A common expression in Paul’s writings (chs. 4:1; 6:1; etc.).

Is God unrighteous? In the Greek the form of this question implies that the answer must be negative.

Who taketh vengeance. Literally, “who brings on the wrath,” that is, who brings on the divine displeasure against sin (see on ch. 1:18).

I speak as a man. Compare Rom. 6:19; Gal. 3:17. Paul’s sense of reverence seemed to call for an apology for his outspoken analogy between things human and divine.