Authentic Supplication Number 71.

It is reported by way of ‘Al-Bara’ that the Prophet  said Sawwoo sufoofakum la takhtalifu quloobukum (86).

Footnotes.
(86) Straighten your rows [so that] your hearts do not differ.

Reporters.
Reported by Ad-Darami. It is also in Al-Albani’s Saheeh ‘Abi Dawood as #670. Al-Albani said that it was also in Ahmad, An-Nisa’ee, Ibn Hibban, Al-Hakim, and Bayhaqi. He also said that it was sound in his Saheeh Al-Jami` As-Sagheer wa Ziyadatih, #3648.