A.T. Robertson Commentary 1 Corinthians 2:16

"For who hath known the mind of the Lord, that he should instruct him? But we have the mind of Christ." — 1 Corinthians 2:16 (ASV)

For who hath known the mind of the Lord (Τις γαρ εγνω νουν Κυριου; ). Quotation from Isa 40:13.

That he should instruct him (ος συνβιβασε αυτον). This use of ος (relative

who ) is almost consecutive (result). The πνευματικος man is superior to others who attempt even to instruct God himself. See on Ac 9:22; 16:10 for συνβιβαζω, to make go together.

But we have the mind of Christ (ημεις δε νουν Χριστου εχομεν). As he has already shown (verses 6-13). Thus with the mind (νους. Cf. Php 2:5; Romans 8:9,27). Hence Paul and all πνευματικο men are superior to those who try to shake their faith in Christ, the mystery of God. Paul can say, "I know him whom I have believed." "I believe; therefore I have spoken."