Anas bin Malik reported,

The Prophet ﷺ stood in prayer until his feet, or his shins, became swollen. It was said to him, "Messenger of Allah, has not Allah forgiven you your past and future sins?"He replied, "Should I not then be a grateful servant?"

Azami 2664

Sahih

عن أنس بن مالك، قال

قام النبي ﷺ حتى تورمت قدماه، ساقاه. قال: فقيل: يا رسول الله، قد غفر الله لك ما تقدم من ذنبك وما تأخر؟ قال: أفلا أكون عبدا شكورا.

الأعظمي 2664صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Prayer
Chapter
Minor actions do not invalidate the prayer
Section
Striving of the Prophet ﷺ in night prayer to raise ﷺ in ranks and elevate in status
Numbering
Jami al-Kamil 2664 (2nd edition)
Azami 2664