Nahj al-Balāgha

Hadith 1801
good-tempertrials-afflictions
٢١٧. وَقَالَ (عليه ‏السلام): فِي تَقَلُّبِ الْأَحْوَالِ عِلْمُ جَوَاهِرِ الرِّجَالِ.
217. Amīr al-mu’minīn, peace be upon him, said: Through change of circumstances the mettle of men is known.
Source: al-Sharīf al-Raḍī