Meet Zadok. He is the hero of The Walls of Arad, the third book in the “Journey to Canaan” series. Zadok is a shepherd—specifically, he is the shepherd of the Tabernacle flock. He has a gentle heart, one that Miriam decides is perfect for our heroine, Arisha. (You’ll meet her later.) Ancient shepherds have a complicated history. In Abraham’s day, they …