Sahih Bukhari
Sales and Trade
Volume: 003 / Book Number: 034 / Hadith Number: 430
Narrated Abu Huraira:
The Prophet said, "Allah says, 'I will be against three persons on the Day of Resurrection:
1. One who makes a covenant in My Name, but he proves treacherous.
2. One who sells a free person (as a slave) and eats the price,
3. And one who employs a laborer and gets the full work done by him but does not pay him his wages.' "