“You shall give him his wages on the same day” (v15). The laws of Deuteronomy tried to limit harm, promote justice, and protect the vulnerable in a sinful world. Divorce was regulated to protect women (v1-4), and those with the means to hire others were told to be sensitive to their precarious situation and pay them promptly. Also, instead of claiming everything that was “rightfully” theirs, land owners were to leave some harvest for the poor and foreigners (v19-22).
“You shall remember …” (v22). The basis for our merciful of treatment of others is remembering that God has been overwhelming merciful to us.