Sahih Adab al-Mufrad

Sayyiduna Abu Darda narrates from the Prophet (ﷺ) that he (ﷺ) said: "Shall I not tell you of something even better in rank than prayer, fasting, and charity?" The people said, "Certainly." He (ﷺ) said: "Reconciling between people, and on the contrary, spreading discord among people—this (habit) shaves off (faith)."

Sayyiduna Ibn Abbas (may Allah be pleased with him) said regarding the Qur’anic verse «فَاتَّقُوا اللَّهَ وَأَصْلِحُوا ذَاتَ بَيْنِكُمْ» “Fear Allah and make reconciliation among yourselves”: This is a command from Allah that is obligatory upon the believers, that they should fear Allah and make reconciliation among themselves.