Sunan Ibn Majah 994
سنن ابن ماجه#994SahihSimak bin Harb narrated that he heard Nu’man bin Bashir say:“The Messenger of Allah (ﷺ) used to straighten the rows until he made them like a spear or an arrow-shaft. Once he saw a man’s chest (sticking out) so the Messenger of Allah (ﷺ) said: ‘Make your rows straight or Allah will create division among you.’”
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Zubair Ali ZaiSahih Muslim
In-book reference: 5:192