Hadith 106

Riyad as-Salihin

Book 8: The Book of Virtues

Chapter 194

The Excellence of Standing in the First Row (In Salat)

باب فضل الصف الأول والأمر بإتمام الصفوف الأُول، وتسويتها والتراص فيها

Riyad as-Salihin 1096
وعن أبي هريرة رضي الله عنه قال قال رسول الله صلى الله عليه وسلم‏:‏ ‏ ‏ ‏(‏‏(‏رواه أبو داود‏)‏‏)‏‏.‏
"‏وسطوا الإمام، وسدوا الخلل‏"
Abu Hurairah (May Allah be pleased with him)reported:

The Messenger of Allah (ﷺ) said, "Let the Imam stand in the middle (so that those praying behind him should be standing both on his right and his left) and close the gaps."[Abu Dawud].