Matthew Poole and continuators on Job 31:7

7. If my step hath turned out of the way , and mine heart walked after mine eyes , and if any blot hath cleaved to mine hands:

If I have wittingly and willingly, and customarily (as you accuse me) swerved from the way of truth and justice which God hath prescribed to me: For otherwise no man here is so just, but he sometimes takes a wrong step, Eccles. 7. 20.

If I have let my heart loose to covet and seek after forbidden things which mine eyes have seen; which may design either 1. the lust of uncleanness. But of that he had spoken v. 1. and reneweth the discourse v. 9. Or rather 2. the lust of Covetousness, which is called the lust of the eyes, 1 John 2. 16. partly because it is oft caused by sight, as Ios. 7. 21. and partly because oft-times all the satisfaction it gives, is to please the sight, Eccles. 5. 11. And this sin is most legible in the following punishment, v. 8. where his loss answers to this evil gain. The Phrase notes the common method and progress of sin, which is to enter by the eye to the heart, Gen. 3. 6. Num. 15. 39. Eccles. 2. 10. & 11. 9.

Or, blemish, to wit, any unjust gain. If I have in my hands or possession any Goods gotten from others by fraud or violence, which would be a great scandal and a blot to my reputation.