Comentario sobre Deuteronómio 24:13

כבוא השמש [THOU SHALT RESTORE HIM THE PLEDGE] WHEN THE SUN GOETH DOWN — if it be a night garment; whilst if it be a garment worn during the day restore it to him in the morning. This, indeed, has already been written in the section beginning with the words ואלה המשפטים (Exodus 22:25) “Restore it unto him till the going down of the sun” which means: restore it unto him for the whole day and at nightfall you may take it again [till the daybreak of the next morning] (Bava Metzia 114b; cf. Rashi on Exodus 22.25.2 and Note thereon).

ולך יהיה צדקה, ”and it shall be accounted as a righteous act for you;” if you restore the pledge to that debtor. If after thirty days of your doing this the debtor still has not paid up, the court will sell it and give the proceeds to the creditor. If it was sold for more than what was owed, the surplus is given back to the debtor. (Talmud, tractate Baba Metzia, folio 114a).

וברכך AND HE WILL BLESS THEE — and even if he will not bless thee, in any case, ולך תהיה צדקה IT SHALL BE RIGHTEOUSNESS UNTO THEE [BEFORE THE LORD THY GOD] (Sifrei Devarim 277:4).

ביומו תתן שכרו, “you are to pay him his wages on the day he performed the work.” In order that he can use the money forthwith. ולא תבא עליו השמש, “and the sun must not set on it;” i.e. for your benefit.
The words: “on its day you shall pay his wages,” are part and parcel of the line “so that he will not call out against you to the Lord.” The whole verse must be understood thus: “you must pay him his wages on the same day for he is a poor man, his life depends on his getting his wages immediately; do not allow the sun to set before you pay him so that he will not appeal against you to G’d. If that were to happen you will be at risk by nightfall as at that time the attribute of Justice commences its reign and it will be poised against you.”