Musnad Ahmad 28:418

'Abd al-Razzaq narrated to us, Ma'mar informed us, from 'Asim ibn Abi al-Najud, from Khaythama ibn 'Abd al-Rahman, from 'Abdullah ibn 'Amr ibn al-'As, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Indeed, when the servant is upon a good path of worship, then he becomes ill, it is said to the angel assigned to him: 'Write for him the like of his deeds when he was free, until I release him or take him to Myself.'"