the prophet ﷺ used to straighten us in the rows of prayer as the arrow is straightened, until he thought that we had learned it from him and understood it. One day he turned towards us, and shoulders in order, and say; Do not be irregular. And he would say: Allah and his Angels bless those who near the first rows.  

سَمِعْتُ النُّعْمَانَ بْنَ بَشِيرٍ يَقُولُ كَانَ النَّبِيُّ ﷺ يُسَوِّينَا فِي الصُّفُوفِ كَمَا يُقَوَّمُ الْقِدْحُ حَتَّى إِذَا ظَنَّ أَنْ قَدْ أَخَذْنَا ذَلِكَ عَنْهُ وَفَقِهْنَا أَقْبَلَ ذَاتَ يَوْمٍ بِوَجْهِهِ إِذَا رَجُلٌ مُنْتَبِذٌ بِصَدْرِهِ فَقَالَ لَتُسَوُّنَّ صُفُوفَكُمْ أَوْ لَيُخَالِفَنَّ اللَّهُ بَيْنَ وُجُوهِكُمْ  

[Machine] The Messenger of Allah ﷺ used to align us in rows until it was as if he was walking with us, touching our chests. When he wanted to make the takbir (proclamation for prayer), he saw a man whose chest was protruding, so he said, "Line up your rows or Allah will cause divisions among your faces."  

كَانَ رَسُولُ اللهِ ﷺ يُسَوِّينَا فِي الصُّفُوفِ حَتَّى كَأَنَّمَا يُحَاذِي بِنَا الْقِدَاحَ فَلَمَّا أَرَادَ أَنْ يُكَبِّرَرَأَى رَجُلًا شَاخِصًا صَدْرُهُ فَقَالَ لَتُسَوُّنَّ صُفُوفَكُمْ أَوْ لَيُخَالِفَنَّ اللهُ بَيْنَ وُجُوهِكُمْ