Straightening the saffs

Q: When two people pray together, should the follower stand next to and parallel to the imam, or should he stand slightly behind? I have heard conflicting opinions regarding this.

Q: My question regarding the small distance which is left between muqtadis during Salaah due to pillar between the saff whether we should leave the gap or stand there which leads to disturbing the straightness of the saff?

Q: Can a child stand with the man in the same row for Salaah. Does the child have to stand in a separate row. Is there any harm for the child to stand with the men. Mufti saheb if there is any hadeeth or reference please do mention it.

Q: Please explain the procedure of stepping forward to fill in a gap in the saff in front. Because beheshti zewar mentions to step past the sajdah position breaks the Salaah.

Q: The following categories of Muqtadis are present for a Jamaat Salaat: Mature males, Immature males, Mature females and Immature females. What will be the order in which the sufoof (rows) are arranged?

Q: How should na-baaligh children be arranged in the suffs of the Masjid during Salaah?

Q: If the time for Fajr salaah in the masjid /musallah is up, and there is only the muazzin and imam present, but someone arrives just then but still needs to make wudhu and read sunnats. Should the muazzin stand behind the imam because they know there is another musallee that will join the salaah later, or should he stand on the right of the imam and when the musallee comes to join then move back to the saff?

Q: My question is about a random salafi brother that came up to me after Salah and he is like you should not have stood alone at the back your Salah is not accepted. I believe its Makrooh to stand alone in a Saaf. There was no space and later someone joined as well. I just wanted dalil for my self not for anyone else. I got very irritated because I could see he was just bringing up issue after issue. Allhumdulilah I read your fatwas everyday, he went on after that talking about where we place our hands and he was like Walahi the hadith is daaif about Ali Radhiallahu anho. I was so shocked he was taking Qasam on everything. I have read proofs from your website about the hands. My main concern is my intention. I am going to be starting Alim course soon. Could you explain the type of intention I should have when studying and coming across people like this. I know everything is for the sake of Allah. But I felt very angry towards this person more then anything and I had this feeling which was from shaitaab to prove him wrong.

Q: If one is reading salaah in jamaat and a musalli in the saff ahead leaves the jamaat due to breaking wudhu can one fill the gap from the saff behind, as he will go ahead of the place of sajda. What happens to salaah should he repeat?

Q: I lead the prayers in the Masjid. Many people stand with there children in the first saff. The children are under 9. When I tell them make the children stand at the back they do not listen. What is the Shar'iee hukm? Is it makruh for them to stand in first saff? Are they allowed to stand in second saff or they should stand in last row on the left side? Please give me reference from Hadith so I could explain to them and also if they do not listen how should I advise them?