Always carry a heart of purity and do not dabble with impurity.
Both pure and impure things are evident but in between them there are doubtful things and most of the people have no knowledge of their purity. So whoever saves himself from these suspicious things saves his religion and his honor. And whoever indulges in these suspicious things is like a shepherd who grazes his animals near the private pasture of someone else and at any moment he is liable to get in it. O people! Beware! Every king has a private pasture and the private pasture of Allah on the earth are the things He has forbidden. Beware! There is a piece of flesh in the body if it becomes good the whole body becomes good but if it gets spoilt the whole body gets spoilt and that is the heart. – Prophet Muhammed, as narrated in Sahih Bukhari (2:49)
