Mustadrak al-Hakim — Hadith 3116

It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) concerning this saying of Allah Almighty, "And those who are patient in al-ba'sa', al-darra' and at the time of al-ba's" [Surah al-Baqarah: 177], that he said: "Al-ba'sa'" means poverty and hardship, "al-darra'" means illness and affliction, and "hin al-ba's" means the time of fighting and battle.
This hadith is sahih (authentic) on the condition of Imam Muslim, but the two Shaykhs (Bukhari and Muslim) did not record it.