Sahih Al Bukhari – Book of Patients
Volumn 007, Book 070, Hadith Number 575.
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Narated By Anas bin Malik : The Prophet said, "None of you should wish for death because of a calamity befalling him; but if he has to wish for death, he should say: "O Allah! Keep me alive as long as life is better for me, and let me die if death is better for me.'"
