It wasnarrated that Anas bin Malik said:
"The Messenger of Allah(ﷺ)said: 'Make your rows straight, for straightening the rows ispartof completing the prayer.'" (JA)
English reference (JA): Vol. 1, Book 5, Hadith 993 (JA)
Arabic reference (JA): Book 5, Hadith 1046 (JA)