It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The believer is a source of affection, and there is no good in one who neither shows affection nor is shown affection."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 21097