This narration is to be understood as referring to one who became Muslim in the month of Ramadan and missed that because of an obstacle such as illness or other than that, or he was among those who did not know that fasting was obligatory upon him, so he broke the fast, then after that he learned of its obligation upon him; making it up becomes binding upon him. What indicates that is that Imam عليه السلام said: “Let him make up what he missed,” and missing does not occur except after the obligation has become directed toward the morally obligated person. And whoever became Muslim halfway through the month of Ramadan, what had passed was not directed toward him except on the condition of Islam, and for that reason making it up was not binding upon him. The Shaykh (Al-Mufid), may Allah سبحانه وتعالى have mercy upon him, said: “When a person dies and he had fasted part of the month of Ramadan, then it is appropriate for the eldest of his male children to make up the fasting on his behalf.”
Commentary #1