Humayd bin Abd al-Rahman narrates from his mother, Umm Kulthum bint Uqbah (may Allah be pleased with her), who was among the early Emigrants, that she said: I heard the Messenger of Allah (peace and blessings be upon him) saying: "The one who reconciles between people is not a liar; he says something good."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20831