My witness is in heaven - That is, I can appeal to God for my sincerity. He is my witness; and he will bear record for me. This is an evidence of returning confidence in God - to which Job always returns even after the most passionate and irreverent expressions. Such is his real trust in God, that though he is betrayed at times into expressions of impatience and irreverence, yet he is sure to return to calmer views, and to show that he has true confidence in the Most High. The strength, the power, and the point of his expressions of passion and impatience are against his "friends;" but they "sometimes" terminate on God, as if even he was leagued with them against him. But he still had "permanent" or "abiding" confidence in God.
My record is on high - Margin "in the high places." It means, in heaven. Luther renders this, und der mich kennet, ist in der Hohe - and he who knows me is on high. The Hebrew is שׂהדי śâhêdı̂y - "my witness;" properly an eye witness. The meaning is, that he could appeal to God as a witness of his sincerity.

My witness is in heaven - I appeal to God for my innocence.

Also now, behold, my (t) witness [is] in heaven, and my record [is] on high.
(t) Though man condemn me, yet God is witness of my cause.

Also now, behold, my witness is in heaven,.... That is, God, who dwells in the heavens, where his throne is, and which is the habitation of his holiness, and from whence he beholds all the sons of men, and their actions, is the all seeing and all knowing Being; and therefore Job appeals to him as his witness, if he was guilty of the things laid to his charge, to bear witness against him, but if not to be a witness for him, which he believed he would, and desired he might:
for my record is on high; or "my testimony"; that can testify for me; who is an "eyewitness" (k), as some render it, before whom all things are naked and open; who has seen all my actions, even the very inmost recesses of my mind, all the thoughts of my heart, and all the principles of my actions, and him I desire to bear record of me; such appeals are lawful in some cases, which ought not to be common and trivial ones, but of moment and importance, and which cannot well be determined in any other way; such as was the charge of hypocrisy against Job, and suspicions of his having been guilty of some notorious crime, though it could not be pointed at and proved; see 1-Samuel 12:3, 2-Corinthians 1:13.
(k) "oculatus meus testis", Schultens.

Also now--Even now, when I am so greatly misunderstood on earth, God in heaven is sensible of my innocence.
record--Hebrew, "in the high places"; Hebrew, "my witness." Amidst all his impatience, Job still trusts in God.

Witness - Besides the witness of my conscience, God is witness of my integrity.