What is the difference between source and evidence

Sources may be someone's personal viewpoint of what happened, and may be made up by the person.Evidence expresses facts about the past.

The founder of the byzantine  empire  and its first  emperor,  constantine  the great,  movedthe  capital of the roman empire  to the city of byzantium in 330 ce, and renamed it  constantinople.  constantine  the great also legalized christianity, which had previously been persecuted in the  roman empire.