And if he wishes, he may pray six rakʿahs, for Ibn ʿUmar said: “When the Prophet ﷺ had completed the Friday prayer, he would move forward and pray two rakʿahs, then move forward again and pray four.”

The right to any spot in the mosque belongs to the person who arrives first in person. What some people do—reserving a place by putting down a prayer-rug, a stick, or a pair of sandals and then coming late, thereby depriving an earlier arrival of that space—is impermissible. Some scholars have even stated that whoever reaches the mosque may remove whatever was placed there and pray in that location, because the one who comes first deserves to pray in the first row, and cordoning off a place in the mosque without being physically present is an act of usurpation.

Shaykh al-Islam Ibn Taymiyyah (d. 728 AH) said: “Many people send mats and the like to the mosque on Friday before they themselves arrive; this is forbidden by unanimous agreement among Muslims—indeed, it is unlawful. As for the validity of praying on such a mat, the scholars hold two opinions, for the person has seized a spot in the mosque by spreading that mat and has prevented other worshippers who preceded him from praying there. What the Law requires is that a man precede to the mosque himself. When he dispatches a mat and then delays his own arrival, he violates the shariah in two ways: first, by arriving late when he has been commanded to come early; and second, by usurping part of the mosque and obstructing those who came before him from completing the first row and the rows after it. Then, when he finally shows up, he proceeds to step over people’s necks.” End of quote.}