question #3 Sahih al-Bukhari 6471, Book 81, Hadith 60 : What is the relationship between physical acts of worship and expressing gratitude to Allah in Islam?

The Prophet (ﷺ) used to pray so much that his feet used to become edematous or swollen, and when he
was asked as to why he prays so much, he would say, “Shall I not be a thankful slave (to Allah)?”