Most scholars—including a report from Ahmad—held that the prayer of one who stands alone behind the row is valid, whether he has an excuse or not, even if there is space in the row.

Some scholars said that the matter requires further distinction: if he has an excuse, the prayer is valid; but if he has no excuse, the prayer is not valid.

The majority cited as evidence that this worshipper prayed with the congregation and did what he was commanded to do. The Prophet, peace and blessings be upon him, said: “The imam has only been appointed to be followed.” (1) He did follow his imam, saying the takbir when he said it, and so on.

They also argued that when the Messenger, peace and blessings be upon him, moved Ibn Abbas to his right, Ibn Abbas stood alone for a brief moment. Yet anything that invalidates the prayer does so whether it is extensive or slight, such as ritual impurity. Thus, if standing alone had invalidated the prayer, Ibn Abbas’s prayer would have been invalid.

They answered the hadith, “There is no prayer for one who prays alone behind the row,” (2) by saying that this negation is a negation of completeness, like the saying: “There is no prayer when food is present, nor while one is resisting the two excretions.” (3) It is known that if a person prays when food is present, his prayer is valid; and if he prays while resisting the two excretions—urine and feces—his prayer is valid.

As for the report that the Prophet, peace and blessings be upon him, “saw a man praying behind the row and instructed him to repeat the prayer,” (4) they answered that the soundness of this hadith is subject to scrutiny. Even if it is sound, perhaps there was some other factor that required the Prophet, peace and blessings be upon him, to instruct him to repeat the prayer. This was a particular incident, and we cannot state with certainty that the reason was his having prayed behind the row.