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?'" (PT)
English reference (PT): Vol. 1, Book 5, Hadith 1419 (PT)
Arabic reference (PT): Book 5, Hadith 1484 (PT)