In this thesis, Sheikh Abd al-Rahman bin Muhammad bin Ali Al-Harfi discusses the entirety of the provisions of fasting and begins his letter by defining fasting and its virtues and the virtues of the blessed month of Ramadan, then presents an explanation of the evidence for the obligation of fasting, then explains the virtue of night prayer, then shows the invalidators of fasting, then concludes his message with some provisions related to eating and drinking, forgetting During the day in Ramadan.