Closing the Gaps and Straightening the Rows in Congregational Prayer

Question:
Doctor, is it obligatory to close the gaps between the rows of people praying in congregation?

Answer:
Yes, it is obligatory that there be no gaps between the worshippers. It is not permissible for there to be gaps between them; rather, they should be close together. So if a person finds a gap, it becomes confirmed for him that he must close it. This carries a great virtue. This is the best of the steps a person takes: to take steps to close a gap in the row. This is confirmed. As for whether it is obligatory, I do not know—meaning, I do not know if it is obligatory—but it is confirmed to be a confirmed Sunnah with a great virtue. It is incumbent upon the worshippers, or it is obligatory for the worshippers, to close the gaps. The Prophet (peace and blessings be upon him) used to urge closing the gaps and filling the holes, and he informed that Satan enters through the gaps in the rows. If the men are close together, no gaps remain for Satan. But some of the brothers misunderstand this.
They think that closing the gaps means spreading one’s legs and squeezing the person next to him. That is not closing the gaps. Closing the gaps means being close together. A person stands in a normal position, without spreading his legs to bother people. But he pulls his brother next to him to be close to him. That is the meaning of closing the gaps. As for spreading one’s legs, taking up space in the row, and squeezing the person next to him on this side and that side, that is an exercise of independent legal reasoning in the wrong place. Yes.