visitors were actually angels bringing them a message from god, and it did come to pass, sarah gave birth to the child she had wanted for so long, a son named isaac. his descendents became the jewish people. >> narrator: next, a family feud that are stretches back plin ya as our journey around the world and across time continues. when back to the beginning with christian yan amanpour returns -- christiane amanpour returns. ♪ push it. ♪ p...push it real good! ♪ ♪ ow! ♪ oooh baby baby...baby baby. if you're salt-n-pepa, you tell people to push it. ♪ push it real good. it's what you do. ♪ ah. push it. if you want to save fifteen percent or more on car insurance, you switch to geico. it's what you do. ♪ ah. push it. i'm pushing. i'm pushing it real good!