Majma al-Zawaid — Hadith 12972

This is reported from him; he says: When two men who have entered Islam cut themselves off from one another, one of them leaves Islam until he returns to that which he left, and his returning is that he comes to the other person and greets him with peace.
Al-Tabarani recorded it; its narrators are the narrators of the Sahih, except Ismah bin Sulayman, who is thiqah (trustworthy).