Islam has defined a set of rules on labor and the labor force. An employer, according to Islamic teachings, must establish a just and cordial relationship with his employees and labor force. Such a relationship must be based on equality, goodwill and the brotherhood of Islam. This is based on the Hadith of Allah's Messenger :
Your workers and slaves are your brothers whom Allah has placed under you. Whosoever has one under him he should feed him of what he eats, clothe him of what he clothes himself, and must not burden them over their ability. But if you do burden them, then help them.
Furthermore, Islam upholds the honor and the dignity of the workers. Allah's Messenger is reported to have said,
"The best of income is that which results from honest labor.
Moreover, Islam requires an employer to declare the wages to the worker before the worker embarks on the required work. (Baihaqi and Abdul Razzaq in al-Musannaf.)
Allah's Messenger has assured the rights of the worker and his wages he is going to receive. Allah's Messenger is reported to have said,
I am the adversary of three people on the Day of Requital: one who gave in my name and then was treacherous, one who enslaved free man and consumed the price and a man who employs a worker but does not pay him his rightful wages.
Allah's Messenger has instructed the employer to pay the wages of his worker before his sweat dries out. Ibn Majah, Hadith no. 2468.