بِسْمِ اللهِ الرَّحْمنِ الرَّحِيمِ
The Messenger of Allah (صلى الله عليه وسلم) said:
"The similitude of good company and that of bad company is that of the owner of musk and of the one blowing the bellows. The owner of musk would either offer you some free of charge, or you would buy it from him, or you would smell its pleasant fragrance; and as for the one who blows the bellows (i.e., the blacksmith), he either burns your clothes or you smell a repugnant smell."
[Al-Bukhari & Muslim]