John Gill's Exposition of the Whole Bible
Deuteronomy 22:3
In like manner shall thou do with his ass,.... As with his ox or sheep when astray, and found, keep it until it is owned, and then restore it; this is expressly mentioned in Exodus 23:4
and so shalt thou do with his raiment; if that is lost and found, it must be restored to the owner, he describing it; a garment is particularly mentioned, it is said a, because in every garment there is a mark or sign by which the owners can inquire about it; for it is made by the hands of men, and does not come from anything common:
and with all lost things of thy brother's, which he hath lost, and thou hast found, shalt thou do likewise: this comprehends everything that is lost, that is properly so; it is asked b;
"what is a lost thing? if a man finds an ox or a cow feeding in the way, this is not a lost thing; an ass whose instruments are inverted, and a cow running among the vineyards, this is a lost thing:''
thou mayest not hide thyself: from seeing it and taking care of it, in order to restore it to the right owner; or dissemble a sight of it, and pretend he never saw it, and so entirely neglect it. In some instances the Jews allow they were not obliged to take any notice or care of it, as,
"if a man find a cow in a cow house (which is not shut), he is not obliged (to take care of it); if in a public place, he is obliged; if it is in a burying ground he may not defile himself for it c.''
a Bartenora in Misn. Bava Metzia, c. 2. sect. 5. b Misn. ib. sect. 9. c Ib. sect. 10.