Assalamu alaykum everyone.
Ive heard stories since a child that once, Abu Talib and our beloved Prophet PBUH were traveling for trade reasons. During the travel they meet a chrisitian priest. Some people say this priest is named Bahira some Gergiz but Im not sure. So they say one he saw the Prophet he immediately invited him and Abu Talib to his house. There he said that Muhammad PBUH is prophesised in the older books. He also makes a mention of a sign having to do with the Prophets shoulder or something.
How true is this story? Which hadiths or historical reference mentions this?
Thank you, Assalamu alaykum, once more.