It is narrated from Sayyiduna Abu Umamah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Indeed Allah, the Mighty and Majestic, has taken me as His khalil (intimate friend), just as He took Ibrahim (peace be upon him) as a khalil, and indeed my khalil is Abu Bakr (may Allah be pleased with him)."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7785