"That which you have been given is but a fleeting comfort of this life. Better and more enduring is that which Allah has for those who believe and put their trust in Him; who avoid gross sins and indecencies and, when angered, are willing to forgive; who obey their Lord, attend to their prayers, and conduct their affairs by mutual consent; who bestow in alms a part of that which We have given them and, when oppressed, seek to redress their wrongs. [Al-Qur'an, Sura: 42 (Ash-Shura), Ayat: 36-39] "
"It is a mercy from Allah that you were gentle with them. If you had been rough or hard of heart, they would have scattered from around you. So pardon them and ask forgiveness for them... (Aal `Imran 3:159)"
"Prophet Mohammad's (pbuh) Jewish neighbor used to throw his garbage at the door step of the prophet's (pbuh) home every morning . The Prophet (pbuh) would then pick it up and throw it in the disposal area along with his personal trash, but the Prophet (pbuh) never got angry. One day, there was no garbage and the Prophet (pbuh) went to see if the man was ill. The man was so impressed that he became a friend. Our Prophet (pbuh) then started taking care of his neighbor and the Jewish neighbor very soon embraced Islam." (Bukhari)
The Messenger of Allaah (peace and blessings of Allaah be upon him) said: "The strong man is not the one who can overpower others (in wrestling); rather, the strong man is the one who controls himself when he gets angry." (Reported by Ahmad, 2/236; the hadeeth is agreed upon).