question #3 Sahih al-Bukhari 1130, Book 19, Hadith 10 : What lessons can be learned from the Prophet’s commitment to prayer despite physical discomfort?

The Prophet (ﷺ) used to stand (in the prayer) or pray till both his feet or legs swelled. He was asked why
(he offered such an unbearable prayer) and he said, “should I not be a thankful slave.”