In Al-Zuhd al-Nabi it is narrated that God's Prophet (a.s) was asked
“What is the best thing that is given to a man?” He said: “Good temper.”
من كتاب زهد النبي (صلى الله عليه وآله): سئل رسول الله (صلى الله عليه وآله) ما أفضل ما أعطي الإنسان؟ فقال: حسن الخلق.
Similar narrations
Mīzān al-Ḥikma #385The Prophet (SAWA) said, ‘The best thing given to a believer is good character, and the worst thing given to a man is a corrupt heart in a...