Matthew Henry Presbyterian @wholebiblehenry

Job's discourse here is called a parable (mashal), the title of Solomon's proverbs, because it was grave and weighty, and very instructive, and he spoke as one having authority. It comes from a word that signifies to rule, or have dominion; and some think it intimates that Job now triumphed over his opponents, and spoke as one that had baffled them.

Commenting on Job 27:1-6

John Gill Reformed Baptist @doctorgill

My righteousness I hold fast, and will not let it go,.... Meaning not his personal righteousness, or the righteousness of his works, as his justifying righteousness before God, and for acceptance with him; which no man that is convinced of the insufficiency of, as Job was, will hold fast, but renounce, and desire, with the Apostle Paul, not to be found in it, Phi 3:9.

Jamieson-Fausset-Brown Reformed @jfbcommentary

Rather, my "heart" (conscience) reproaches "not one of my days," that is, I do not repent of any of my days since I came into existence [MAURER].