while they are praying today’s noon prayer. This is valid, because one making up a prayer is praying behind one performing it on time. The prayer is the same; only the time differs.
The reverse is also valid: one who is making up a prayer may lead one who is performing it on time. Thus, the imam is the one making it up, while the follower is the one performing it on time.
For example, a man remembers that he missed yesterday’s noon prayer and says to another person, “I will pray yesterday’s noon prayer, so pray today’s noon prayer with me.” The imam prays yesterday’s noon prayer, while the follower prays today’s noon prayer. Thus, the imam is making up the prayer and the follower is performing it on time. Therefore, a prayer performed on time is valid behind a made-up prayer, and vice versa, because the prayer is the same; only the time differs.
ONE PERFORMING AN OBLIGATORY PRAYER BEHIND ONE PERFORMING A VOLUNTARY PRAYER, ........
His statement, “Not one performing an obligatory prayer behind one performing a voluntary prayer,” means that it is not valid for one offering an obligatory prayer to follow one offering a voluntary prayer. Thus, the imam may not be offering a voluntary prayer while the follower is offering an obligatory one.
The evidence for this is as follows:
1 — The Prophet (peace and blessings be upon him) said: “The imam has only been appointed to be followed, so do not differ from him” (1). This constitutes differing from him, because the follower is offering an obligatory prayer while the imam is offering a voluntary one.
An example is a man who wishes to pray two units of a sunnah prayer. Another man then comes and says, “I shall pray the dawn prayer with you.” The imam prays the sunnah prayer, while the follower prays the dawn prayer. We say that the follower’s prayer is invalid.
2 — In this case, the follower’s prayer is of a higher degree than the imam’s prayer, and it is not appropriate for that which is higher to be prayed behind that which is lower. This is the evidence for the view adopted by the author, may Allah have mercy on him, and it is one of the two opinions.