the inscription on the coin was saul invictus, the unconquerable sun, a reference to the sun god whoeally a worshipper of the god of jesus or was he a worshipper of the sun god? >> by that time, of course, christians can ranton millions. and i suppose constantine thought, if you can't beat them, join them. and i think with his mother, too, well, he thought that this is true. >> constantine had an influential mother, helena, a devoted christian. she traveled to the holy land and located the most important sites from the christian story, building great shrines that remain among the holiest christian places today. >> she was a very noble lady, and she led the building program in the holy land to have the church of the holy sepulcher built where jesus was buried and rose from the dead. and also a church built to honor the giving of the our father, the lord's prayer. she had a building program there. and she had the money and his support. >> constantine also found in her faith something that would redeem him. >> he knew christian faith very well, and he knew baptism remitted all your sins