Muhaqqaq Masala

In congregational prayer, stand perfectly straight, close together in such a way that each other's arms are touching and there is no gap or space left in between.

(1) 'An Nu'man bin Bashir qala: Kana Rasulullah (SAW) yusawwi sufufana hatta ka'annama yusawwi bihal qidah - Al Hadith (Sahih Muslim)

Translation: Hazrat Nu'man bin Bashir (May Allah be pleased with him) states that the Messenger of God (Peace be upon him) used to make such arrangements in straightening our rows as if arrows would be straightened by them. (Masail-e-Namaz/Pg: 8)