We start in a place that many of us are thinking about this weekend. Bethlehem. Where the bible tells us that a young woman named mary stopped for the night. And where shepherds, angels and kings with... See More
We start in a place that many of us are thinking about this weekend. Bethlehem. Where the bible tells us that a young woman named mary stopped for the night. And where shepherds, angels and kings with led by an especially bright star to welcome and worship her newborn child. He's the prince of peace, that's what we call him. That's what christmas is all about. And so, every year, 2 million pilgrims are drawn here to the church of the nativity where there is a small cave that marks the humble beginnings of their savior. I'm glad to be here. Do you believe this is where jesus was born? I do. I met alexander and his mother who traveled from north carolina to try to really connect with their faith. I believe it's somewhere here, whether it's right at that spot I don't know. When I go down there into the grotto, I may feel this is the place. But first we must wait. As the greek orthodox caretakers prepare and purify this sacred Down here in this grotto in the church of the nativity is this altar, marked by a silver star and where christians in the tradition says that all of this began, this is where they believe jesus was born. The faithful gathered in this intimate space believe that the birth of jesus here was the fulfillment of a series of predictionss and promises that began more than 2,000 years ago. 70 miles north of bethlehem is the small hill city of nazareth, an old orthodox church marks the spot where it's said the angel gabriel first told the virgin mary that she would bear a savior. I think mary's response to the angels were, is nothing less than startling. Instead of saying, impossible, mary said, bring it on. Let's roll. What took you so long? She had good reason to welcome the angels news. Mary, like jesus was jewish, and for generations, prophets such as isaiah had been tolding the jewish people a messiah would come and lead them to their destiny. Jews were looking for a mighty king and they said the lord will give you a sign. When isaiah said a virgin would conceive and bear a son. Like her old testament ancestors from noah to moses to the prophets, mary answered the call and she's become an icon to more than just christians. In fact, in the koran, she's the only woman who has a chapter dedicated to her. Mary is the most unifying factor within all world religions. Back at the cave beneath the church of the nativity in bethlehem, alexander and his mother treeteresa, get their turn to touch the silver star. It's unbelievable to think that this is where jesus was born. Actually being able to go down and touch the stone, every christmas, what we hear about, before I wasn't really sure about my faith but I'm here and seeing all of this, I love it. It's amazing. The christmas story is all about stars and light. In the gospels a star leads the three wise men, the magi, to the newborn child. At that point in time when new stars were seen usually signified the birth of a prominent person. But could there really have been such a star on the night jesus was born? Scientists do indicate there was extraordinary activity in the skies. But for many scholars, for proof of the star of bethlehem or proost nativity itself, misses the real point. We don't know very much about the historical birth of jesus. We know, however, that the tales that were told are timeless accounts that are powerful and beautiful and still are very moving to the present day. But the story we celebrate this holiday season didn't start here. It actually follows the stories of all our ancient ancestors from the old testament. If you think about it, and it's very hard, the bible is a story of family, a great, epic tale that spans and sprawls across the generations. Like most families, they started off by fighting one another and by making peace. They tried to make rules to live by and to keep them, or at least, to learn from their mistakes. And like every family they were convinced they were special, even when everything was working against them. So to really understand this great family saga, I brought along my son darius as we set off on our biblical detective story. Can I get your exit? Flying high. Look at this. And low above the nile delta in egypt. Don't fall out. Trying not to, at least. What did moses do at mount sinai? He received the ten commandm commandments. We went to archaeological digs. Isn't it so cool zm and unexpected reminders of home. What is the difference between this and the washington monument? We are on a train to cairo. In many ways, darius is the reason I'm on this journey. You see, my mother is a christian from england and my father is a muslim from iran. I married a jewish american. And in my son all three of these great faiths come together. Christiane amanpour in israel. I've spent most of my professional life traveling from conflict to conflict. Where the bloodshed usually has something do with religion. So, we wanted to find out whether these biblical stories that are shared have the power, not just to divide and harm, but to unite and heal. Extraordinary just staring out of the window and you see all these mosques overlaying churches and I think one of the extraordinary things is to realize and remember that christianity, judaism and islam have so much in common. And these three faiths all trace their stories back to the biblical patriarch, back to the beginning.
This transcript has been automatically generated and may not be 100% accurate.