It wasnarrated from Ziyad bin 'Ilaqah that he heard Mughirah say:
"TheMessenger of Allah (ﷺ) stood (in prayer) until his feet becameswollen. It was said: 'O Messenger of Allah, Allah has forgiven youyour past and future sins.' He said: 'Should I not be a thankfulslave?'"
English reference: Vol. 1, Book 5, Hadith 1419
Arabic reference: Book 5, Hadith 1484