question #1 Sahih Muslim 199b, Book 1, Hadith 398 : What is the significance of the special prayer granted to each Messenger?

The Messenger of Allah (ﷺ) said: Every Messenger is endowed with a prayer which is granted and by which he would (pray to his Lord) and it would he granted for him. I have, however, reserved my prayer for the intercession of my Ummab on the Day of Resurrection.