Moses
Leviticus 6:5ESV·traditional attribution

or anything about which he has sworn falsely, he shall restore it in full and shall add a fifth to it, and give it to him to whom it belongs on the day he realizes his guilt.

Matthew Henry Presbyterian @wholebiblehenry

This is the latter part of the law of the trespass-offering: the former part, which concerned trespasses about holy things, we had in the close of the foregoing chapter; this concerns trespasses in common things. Observe here, I. The trespass supposed, Lev 6:2, Lev 6:3.

Commenting on Leviticus 6:1-7

John Gill Reformed Baptist @doctorgill

Or all that about which he hath sworn falsely,.... In all and each of the above cases, in which he had committed a trespass and denied it, and to the denial adds a false oath, and yet after all acknowledges it: he shall even restore it in the principal; whatsoever he has embezzled, or cheated another of, or detained from the right owner, the whole...

Adam Clarke Methodist @methodicalclarke

All that about which he hath sworn falsely - This supposes the case of a man who, being convicted by his own conscience, comes forward and confesses his sin. Restore it in the principal - The property itself if still remaining, or the full value of it, to which a fifth part more was to be added.