On the authority of Abu Hurayrah, from the Prophet, peace and blessings be upon him, who said: "Whoever sends one prayer of blessing upon me, Allah sends ten blessings upon him."(1)

1297 – Ishaq ibn Mansur informed us, saying: Muhammad ibn Yusuf narrated to us, saying: Yunus ibn Abi Ishaq narrated to us, on the authority of Burayd ibn Abi Maryam, who said:
Anas ibn Malik narrated to us, saying: The Messenger of Allah, peace and blessings be upon him, said: "Whoever sends one prayer of blessing upon me, Allah sends ten blessings upon him, and ten sins are erased from him, and he is raised ten degrees."(2)

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(1) Its chain of transmission is authentic. Al-'Ala': he is Ibn 'Abd al-Rahman ibn Ya'qub, the freed slave of the Harqah tribe. It is in "Al-Sunan al-Kubra" under number (1220).
It was also recorded by Muslim (408), and al-Tirmidhi (485), both on the authority of 'Ali ibn Hujr, with this chain of transmission.
It was also recorded by Ahmad (8854), Muslim (408) as well, Abu Dawud (1530), and Ibn Hibban (906) through various routes from Isma'il ibn Ja'far, with it.
It was also recorded by Ahmad (7561) and (10287), and Ibn Hibban (905) and (913) through two routes from al-'Ala', with it.

(2) An authentic hadith, and this chain of transmission is good on account of Yunus ibn Abi Ishaq al-Sabi'i, who – even though Muslim narrated from him – there is some criticism of him that lowers him from the rank of the narrators of the Sahih. It is in "Al-Sunan al-Kubra" under numbers (1221) and (10122).
It was also recorded by Ahmad (11998) and (13754), the compiler in "Al-Kubra" (9807), (10123), and (10124), and Ibn Hibban (904) through various routes from Yunus ibn Abi Ishaq, with this chain of transmission.
Makhlad ibn Yazid contradicted all the narrators from Yunus, for he narrated it – as the compiler recorded in "Al-Kubra" (9808) – from Yunus ibn Abi Ishaq, from Burayd ibn Abi Maryam, from al-Hasan al-Basri, from Anas, with it. Thus he inserted al-Hasan into the chain between Burayd and Anas.
It was also recorded by Abu Ya'la (3681) through the route of Yusuf ibn Ishaq al-Sabi'i, from his grandfather Abi Ishaq, from Burayd ibn Abi Maryam, with it. And its chain of transmission is authentic.
Abu Salamah al-Mughirah ibn Muslim contradicted Yusuf al-Sabi'i, for he narrated it – as the compiler recorded in "Al-Kubra" (9806) – from Abi Ishaq, from Anas, with it, and al-Daraqutni deemed Yusuf's narration correct in "Al-'Ilal" 12/115. =