Sunan an-Nasa'i 810
سنن النسائي#810SahihIt was narrated that An-Numan bin Bashir said:"The Messenger of Allah (ﷺ) used to straighten the rows like shaft of an arrow is straightened before the head is attached to it. He saw a man whose chest was sticking out from the row. I saw the Messenger of Allah (ﷺ) say: 'Make your rows straight or Allah will cause your faces to be deformed
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahHasan Sahih
Al-AlbaniHasan Sahih
Zubair Ali ZaiSahih Muslim
In-book reference: 10:34