Belgariad 1: Pawn of Prophecy (Penguin Random House Children's UK)

Long ago, the evil God Torak fought a war to obtain an object of immense power - the Orb of Aldur. But Torak was defeated and the Orb reclaimed aby Belgarath, the sorcerer. Garion, a young farm lad, loves the story when he first hears it from the old storyteller. But it has nothing to do with him. Or does it? For the stories also tell of a prophecy that must be fulfilled - a destiny handed down through the generations. And Torak is stirring again...