'A man once came and told ?Ali b. al-Husayn (AS) [i.e. Imam Zayn al-Abidin], 'Verily x has said that you are astray and that you are an innovator!' So ?Ali b. al-Husayn (AS) said to him, 'Neither have you observed the right of the man you sat with by transmitting to us what he spoke about, nor have you observed my right by informing me of something about my brother which I would not have known! ... Beware of backbiting for verily it is the food of the dogs of Hell, and know that whoever frequently talks about people's faults, the frequency of his backbiting is a witness [to the fact] that he only finds faults in others according to the extent present in himself.'