If you find that somebody is not grateful for all that you have done for him, then do not get disappointed because often you will find that someone else feels under your obligation though you have done nothing for him and thus your good deeds will be compensated, and Allah will reward you for your goodness.
Ali ibn Abi TalibFear the sins that you commit in secret, because the Witness of those sins is the Judge Himself!
Ali ibn Abi TalibLead such a life, that, when you die, the people may mourn you, and while you are alive they long for your company.
Ali ibn Abi Talib