By the hand of God, i.e. by God's help and inspiration; as God is said to speak to the prophet with or by a strong hand, Isaiah 8:11. I will not teach you my own vain conceits, but what God himself hath taught me. Or, concerning (as the prefix beth is oft used, as Exodus 12:43,44 Psa 63:6 87:3 Proverbs 4:11) the hand of God, i.e. his counsel and providence in governing the world, or the manner of his dealing with men, and especially with wicked men, of whose portion he discourseth Job 27:13,14, &c., showing how far the hand of God is either for them, or upon them, and against them. That which is with the Almighty, i.e. what is in his breast or counsel, and how he executes his secret purposes concerning them; or the truth of God, the doctrine which he hath taught his church about these matters.
Related Commentaries of Job 27:11
Job 27:11
11 I will teach you by the hand of God: that which is with the Almighty will I not conceal.