Halakhah sobre Êxodo 23:4

He prohibited us from ignoring a lost object. Rather we must take it and return it to is owners. And that is His saying, "you may not remain indifferent" (Deuteronomy 22:1). And we have already explained (Sefer HaMitzvot, Positive Commandments 204) about their saying in the Mekhilta (Sifrei Devarim 222:2) regarding the matter of a lost object, "We have found to learn that one transgresses a positive and a negative commandment." And the language of the Gemara (Bava Metzia 30a) is, "Returning a lost object is a positive commandment and a negative commandment." And in Mishneh Torah (Deuteronomy), He repeated the prohibition about this content, and the negative commandment appears in it. And that is His saying, "You may not observe your brother’s ox or his sheep straying." And in the Sifrei (Sifrei Devarim 222:2): "'You may not observe' - that is a negative commandment. And earlier, He says, 'If you encounter, you must surely return' (Exodus 23:4) - that is a positive commandment." And the regulations of this commandment have already been explained in the second [chapter] of [Bava] Metzia. (See Parashat Ki Tetzei; Mishneh Torah, Robbery and Lost Property 11.)

To return a lost item to an Israelite: To return a lost item to its owners, as it is stated (Deuteronomy 22:1), "you shall surely return them to your brother." And in the explanation, they, may their memory be blessed, said (Bava Metzia 30a) [that] returning a lost item is a positive commandment. And this commandment is repeated in another place in the Torah, as it is stated (Exodus 23:4), "When you encounter your [enemy’s] ox, etc., you shall surely return it to (your brother)."