Musnad Ahmad 658:127

Hassan ibn Musa narrated to us, Zuhayr narrated to us, Abu Balj Yahya ibn Abi Sulaym narrated to us, he said: Abu al-Hakam Ali al-Basri narrated to me, from Abu Bahr, from al-Bara’, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Any two Muslims who meet, and one of them takes the hand of his companion, then they praise Allah, they will separate with no sin between them."