Answer: If a Muslim misses prayers unintentionally—because he was asleep, unconscious, or otherwise not in possession of his faculties—and then wishes to make up what he missed, he must do so at once. He should not postpone each missed prayer until the time of its counterpart, as some laypeople do, for Allah says, “And establish the prayer for My remembrance” (20:14). The Prophet ﷺ said, “Whoever forgets a prayer or sleeps through it must perform it when he remembers it; there is no expiation for it other than that.” His words “when he remembers it” are proof that making up missed prayers must be done immediately, in the proper chronological order, without delay. Therefore, attaching every missed prayer to its like at its next appointed time is a mistake.
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Making Up the Prayer After Repentance

Question: A person has neglected most of the obligatory prayers and did not perform them. Later, he wants to repent to Allah, settle what is due, and make up the prayers he missed. What should he do, and is he sinful for what has passed? Kindly advise us—may Allah reward you abundantly.

Answer: After the two testimonies of faith, the prayer is the most emphatic pillar of Islam; it is the second pillar of Islam after the testimonies. Numerous verses and sound hadiths insist on its right, urge believers to guard it, and threaten those who abandon or squander it, all attesting to the prayer’s importance and its lofty status in Islam. It is the backbone of the religion: whoever preserves it will, a fortiori, preserve the rest of his faith and keep away from what Allah has forbidden. Allah the Exalted says, “Recite what has been revealed to you of the Book and establish the prayer; surely the prayer restrains from indecency and wrongdoing” (29:45).