The Prophet ﷺ said to his uncle Abbas, "Uncle, ask Allah often for well-being."
أن النبي ﷺ قال لعمه العباس: يا عم أكثر الدعاء بالعافية.
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Tabarani related it in al-Kabir (11/330–331), and Hakim (1/529), both through the route of Hilal bin Khabab, from Ikrima, from Ibn Abbas, who mentioned it. Hakim said, "Sahih according to the standard of Bukhari." I say, Bukhari did not narrate from Hilal bin Khabab, rather only the four [Sunan compilers] narrated from him, and he is hasan al-hadith.The hadith has also been narrated in the musnad of Abbas. Tirmidhi related it (3514), and Ahmad (1783), and Bukhari in Adab al-Mufrad (726), all through routes from Yazid bin Abu Ziyad, from Abdullah bin Harith, from Abbas, who said, I said, "Messenger of Allah, teach me something to ask Allah for," and he said, "Ask Allah for well-being." So I waited some days, then I came and said, "Messenger of Allah, teach me something to ask Allah for," and he said to me, "Abbas, uncle of the Messenger of Allah, ask Allah for well-being in this world and the next."Tirmidhi said, "This is a sahih hadith, and Abdullah bin Harith bin Nawfal did hear from Abbas bin Abdul-Muttalib." I say, in its chain is Yazid bin Abu Ziyad, and he is daif according to the majority of the scholars.