Deuteronomy 24:14-15

Thou shalt not oppress a hired servant that is poor and needy, whether he be of thy brethren, or of thy sojourners that are in thy land within thy gates: in his day thou shalt give him his hire, neither shall the sun go down upon it (for he is poor, and setteth his heart upon it); lest he cry against thee unto Jehovah, and it be sin unto thee.