question #2 Sahih Muslim 647c, Book 5, Hadith 297 : Why is it discouraged to sleep before the night prayer and to engage in conversation after it?

The Messenger of Allah (ﷺ) delayed the night prayer till a third of the night had passed and he did not approve of sleeping before it, and talking after it, and he used to recite in the morning prayer from one hundred to sixty verses (and completed the prayer at such hours) when we recognised the faces of one another.