Thuwair [and he is Ibn Abi Fakhitah] narrated that :
His father said: Ali took me by the hand and said: 'Come with us to pay a visit to Al-Hasan.' So we found that Abu Musa was with him.' Ali - peace be upon him - said: 'O Abu Musa! Did you come to visit (the sick) or merely (stop by to) visit?' He said: 'No, to visit (the sick).' So Ali said: 'I heard the Messenger of Allah saying: No Muslim visits (the sick) Muslims in the morning, except that sevety-thousand angels, sent Salat upon him until the evening, and he does not visit at night except that seventy thousand angels sent Salat upon him until the morning, and there will be a garden for him in Paradise.