Nahj al-Balāgha

Hadith 1991
asceticism
٣٤. وَقَالَ (عليه ‏السلام): أَشْرَفُ الْغِنَى تَرْكُ الْمُنَى.
34. Amīr al-mu’minīn, peace be upon him, said: The best of riches is the abandonement of desires.
Source: al-Sharīf al-Raḍī