Sahih Bukhari | Volume 3 | Hadith Number 430

Narrated by 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 labourer and gets the full work done by him but does not pay him his wages.'"