Sayyiduna Anas bin Malik (may Allah be pleased with him) said that after the iqamah, the Messenger of Allah (peace and blessings be upon him) turned towards us and said: "Straighten your rows and stand close together with one another. I see you from behind my back."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2289