What is the meaning of the noble Hadith, "There is no prayer for one who prays alone behind the row," and does it include one who could not find a place in the row? And what should be done in this situation?

The meaning of the aforementioned hadith and the different scholarly opinions on the issue have been clarified in Fatwa No. 104711. Sheikh al-Islam Ibn Taymiyyah's choice opinion is that standing in the row is obligatory, but this obligation is waived with an excuse. Thus, whoever finds a place and prays alone must repeat their prayer due to their negligence, whereas whoever does not find a place has a valid prayer and incurs no sin. This is a moderate view that combines the various pieces of evidence.

Accordingly, it is not obligatory to move forward to stand next to the Imam, nor to move backward, nor for others to move backward, to stand with someone who has not found a place. Rather, one should pray alone behind the row as long as they have not found a place, based on Allah's saying: "So fear Allah as much as you are able" (Quran 64:16) and the Prophet's saying: "And when I command you to do something, do of it what you are able." Umm Sulaym indeed prayed behind the row when she did not find a place in the men's row, as explained in the previous fatwa.