Mughira b. Shu'ba reported that Allah's Apostle (ﷺ) worshipped so much that his feet were swollen. It was said to him:(Why do you undergo so much hardship despite the fact that) Allah has pardoned for you your earlier and later sins? Thereupon he said: May I not (prove myself) to be a grateful servant (of Allah)?

English translation · Sahih Muslim