It is said that a man is known by the company he keeps. It is because companionship has a profound effect on a person's moral, social, individual and collective life. It is companionship that makes a person worthy or non-worthy. Abu Musa narrated that the Holy Prophet said:
 The example of a good companion (who sits with you) in comparison with a bad one, is like that of the musk seller and the blacksmith's bellows (or furnace); from the first you would either buy musk or enjoy its good smell while the bellows would either burn your clothes or your house, or you get a bad nasty smell thereof. (Sahih al-Bukhari: 2101)