The Prophet ﷺ said, "No Muslim sends blessings upon me except that the angels send blessings upon him for as long as he sends blessings upon me. So let the servant do little of that or much."
عن النبي ﷺ قال: ما من مسلم يصلي علي إلا صلت عليه الملائكة ما صلى علي، فليقل العبد من ذلك أو ليكثر.
Ibn Majah (907) and Ahmad (15680) both narrated it through Shuba, from Asim bin Ubaydullah, who said, "I heard Abdullah bin Amir bin Rabia narrating from his father," and he related it.Asim bin Ubaydullah bin Asim bin Umar bin Khattab is the Adawi, the Madani, and he is daif, but he has been corroborated. Abdul-Razzaq (3115) narrated it from Abdullah bin Umar, from Abdullah bin Amir bin Rabia, from his father, who said, the Messenger of Allah ﷺ said, "Whoever sends blessings upon me once, Allah will send blessings upon him, so do so much or little of it."Abdullah bin Umar here is the Umari, and he is daif, but combining the two routes, the hadith becomes hasan. Ibn Qayyim said in Jala Afham (p. 142), "The narration of this hadith through these two differing routes indicates that it has a basis, and this does not fall below the middle degrees of hasan, and Allah knows best."Similar in meaning is what was reported from Abdullah bin Masud, that the Messenger of Allah ﷺ said, "The people closest to me on the Day of Resurrection will be those who send the most blessings upon me."Tirmidhi (484) narrated it from Muhammad bin Bashshar, who said, Muhammad bin Khalid bin Uthma narrated to us, who said, Musa bin Yaqub Zami narrated to us, who said, Abdullah bin Kaysan narrated to me that Abdullah bin Shaddad told him, from Abdullah bin Masud, and he related it.Tirmidhi said, "This is a hasan gharib hadith."I say, in its chain is Musa bin Yaqub Zami, about whom there is disagreement, but his hadith is hasan as long as his error does not become apparent. There has been disagreement about him regarding the chain of this hadith in several ways. Daraqutni said in Ilal (5/113), "The confusion in it comes from Musa bin Yaqub, and he cannot be relied upon."Abdullah bin Kaysan is the Qurashi, the Zuhri, and he is obscure.