Bruce Feiler follows the Israelites' 40-year trek through what the Bible calls a "great and terrible wilderness." 

Feiler experiences the stark reality of the Sinai desert, where it's a struggle simply to survive. He finds the locations said to be where God provided water and food for the Israelites - and discovers the secret of the tamarisk tree, which produces a sweet, honey-like substance called "manna." The desert is also a haven for spiritual pilgrims. Feiler visits St. Catherine's Monastery, the oldest operating church in the world. He attends the service, a powerful, unchanged ritual of 1,500 years, and sees what's claimed to be the real "burning bush" from which God spoke to Moses. One of the monks, Texas-born Father Justin, shows him the monastery's renowned library of priceless religious art and manuscripts. Feiler climbs Mt. Sinai, where Moses received the Ten Commandments. As he follows the 40-year route of the Israelites, Feiler travels to the "lost city" of Petra, in Jordan, where the Israelites may have lived for many years. Nearing the end of Moses' journey, Feiler climbs Mt. Nebo, where God showed Moses the Promised Land. At the end of his own journey, Feiler realizes that although Moses was denied entrance himself, it was not the land after all that was important for Moses. It was his meeting with God. (Part 3 of 3)