Even if you observe another individual committing the worst of vices you should not despise him/her, nor should you consider yourself nobler. It is very much possible that the perpetrator of the vice may resort to sincere repentance while the one who despised the sinner become ensnared in the traps of nafs and Shaitan. One has no certainty regarding one’s end. One, therefore has no basis for regarding another with contempt.
Maulana Ashraf Ali Thanwi
Source: Albalagh