Musnad Ahmad 337:3

Yahya ibn Ghaylan narrated to us, he said: Rishdin narrated to us, he said: Yazid ibn Abdullah—meaning Ibn al-Had—narrated to me, from Abu Bakr ibn al-Munkadir, from Ata ibn Yasar, from al-Sa’ib ibn Khallad, from the Messenger of Allah, peace and blessings of Allah be upon him, that he said: "There is nothing that afflicts the believer, even a thorn that pricks him, except that a good deed is written for him because of it, or a sin is removed from him because of it."