:salamext:
There was a man who came to see Rasulullah shollallahu 'alaihi wa sallam and said, "O Rosulullah, teach me the science that can bring me to paradise and away from hell." So Rasulullah shollallahu' alaihi wa sallam said, "Do not spill anger. Surely you will get paradise. "(Narrated by Thobrani, Shohih)
Shaykh Muhammad ibn Saalih Al 'Uthaymeen rohimahullah also said regarding this hadith, "It is not mean he is prohibited to have a sense of anger. Because anger is part of human nature there. But the point is that you should be sabr/patient when it comes a sense of anger, to avoid the anger gives bad impact. Anger is real embers thrown by Satan can chase into the heart sons of Adam. That is why you can see when people are angry then their eyes became red and the veins of their neck stand out and tense. Sometimes even hair loss and falling due to take angry outbursts. And various other things that do not commendable arise behind. So sometimes the perpetrators feel remorse for the deeds they had done."
Note: Shaykh Muhammad ibn Saalih Al 'Uthaymeen rohimahullah said that message in Arabic. A brother translated it into Indonesian language and I translated it again into English. If the translation is not really accurate, that's happened unintentionally.