Israel remains a land of holiness and of controversy -- and not just in political terms.
Almost by the month, religious scholars and historians propose a new way of understanding the life and impact of Jesus Christ. In his new book "The Jesus Dynasty," James Tabor is the latest addition to this hotly contested catalog.
Tabor, a historian with the Religious Studies Department at the University of North Carolina, Charlotte, has spent his entire career studying the life of Jesus. He says his new book is the culmination of 40 years of research.
"I first traveled to the Holy Land with my parents over 40 years ago," Tabor told "Nightline." "It was that experience that set me on my lifelong quest for the historical Jesus."
His conclusions are certain to provoke intense controversy and skepticism among other scholars and followers of the Christian faith. Tabor argues the historical evidence shows that Jesus had a human father, and that he was joined by a fellow messiah.
We took Tabor back to where it all started, the city of Jerusalem, to assess the major claims in his book.
We began our journey at the location of Tabor's most remarkable archaeological discovery: an ancient hillside tomb outside Jerusalem that had been recently ransacked.
Inside, there were compartments hewn from ancient stone where corpses had been laid to rest. They were empty, apart from one that appeared to contain an old newspaper laid out within the chamber. In fact, it was a burial shroud -- a linen fabric into which a corpse would have been placed. Test results proved almost beyond Tabor's wildest dreams.
"We had to believe the unbelievable," he said. "We had stumbled upon the only example of a burial shroud from the first century."
Analysis showed the shroud had contained the remains of a first-century man who died of tuberculosis. In the same tomb, Tabor's group also found an ossuary -- a box used to contain the bones of the deceased -- that had the name Miriam or Mary inscribed upon it. Tabor also believes the recently discovered ossuary of James, which some scholars have dismissed as a forgery, may have also originated in this tomb.
"There's some circumstantial evidence that the ossuary of James, son of Joseph, brother of Jesus, came from this particular tomb," he said. "We have entertained the possibility that this tomb might've been the family tomb of Jesus."
And it's with regard to Jesus' family that Tabor levels his most controversial claim.
"I'm ready to let the average reader know what we scholars actually discuss. And if it's shocking, it's shocking. You don't have to accept it. Jesus had a father."
Did that mean Tabor does not believe in the Virgin Birth of Jesus?
"I don't," he said. "I think all humans have a human father."
Tabor, who studied first- and second-century Rabbinic and Greek texts, suggests a possible name for the human father of Jesus.
"They begin to call Jesus, 'bar Pantera,' son of Pantera," Tabor said. "And we even have an early Greek source. He's a philosopher named Kelsus, who seems to know a bit more about it. He says that Jesus was the son of a man named Pantera, who either was or became a Roman soldier."
The tombstone of Pantera is in Germany, says Tabor.
"Pantera is from Palestine. And he dates 62 years old when he dies ... He's on the frontier in Germany. And if you figure his date and where he was ... he's a teenager. You know, a young man maybe 19 or 20 at the time Mary becomes pregnant," Tabor said.
The suggestion that Pantera may have been the father of Jesus has been proposed before, however.
"It's not some new discovery," said Dr. Donald Carson, an expert in New Testament history from Trinity University in Illinois. "It's presented in the book as this great find that has been suppressed ... But it's been discussed and carefully weighed by centuries of scholars. There is nothing new here except the association of names that go back, at the end of the day, to reports of the enemies of Christianity from the second century. Pantera was an incredibly popular name at the time of Christ."
Carson argues that Tabor's views are shaped by his own materialistic philosophy, which does not allow for any supernatural or extraordinary elements -- such as a Virgin Birth.
"What Dr. Tabor has done is assumed that the whole thing cannot be," Carson said. "It is a sham and therefore the evidence has to be jiggered, it has to be selectively appealed to in order to take away the evidence of God actually doing something in space, time, history. At that point, no amount of evidence will ever convince him unless he's open to the possibility that Dr. Tabor himself is wrong ... and that God has disclosed himself in space, time and history through a man. Namely, Jesus of Nazareth."
If Tabor's book is controversial on the birth of Jesus, it also raises questions about Jesus' early ministry. Tabor suggests there were two messiahs, not one.
Tabor took "Nightline" to a second cave on our visit to Jerusalem -- this time to the East.
The Suba Cave, as it is now known, is the site of a major archaeological dig. Inside the cave are primitive, centuries-old etchings, which Tabor believes depict the life of John the Baptist. The cave also contains thousands of first-century pottery shards.
Tabor suggests that given the number of individuals, who may have been baptized in Suba, it's likely that Jesus, not John, was actually performing the baptisms.
"I like to surprise with my answers," said Tabor. "Are you ready for this? This is John's area but you know text-wise, we have no record of John baptizing here near Ein Kerem and Suba. He's up along the Jordan River in the Jordanian wilderness. The person we have a record of baptizing here is Jesus, Jesus the Baptist."
Tabor believes that, contrary to the New Testament, Jesus and John the Baptist were twin Messiahs. He says that early texts anticipated more than one Messiah and that the practice of baptism suggests that they were acting similarly in their respective ministries.
"It hit me, how this would have electrified the country," Tabor said. "You see, all these predictions of two Messiahs, and we've got two Messiahs on the ground, operating, one in the north -- John the priest -- one in the south -- Jesus the king. And they're baptizing thousands of people."
Carson, however, strongly disagrees. "Now the texts do not say they did it [baptism] at the same place at the same time. If they did, it wouldn't bother me one way or the other. In other words I don't think the Suba cave adds anything to the account in that respect ... Merely numbers of people being baptized by itself doesn't say very much about the relationship of the two men or that they were both Messiahs or anything like that."
According to Carson, John the Baptist is absolutely clear as to Jesus being the one Messiah.
"John the Baptist says that he is not worthy to even undo the sandals of Jesus," Carson said. "When Jesus asks for baptism, according to Matthew's account, John the Baptist says, 'Wait a minute, I should be baptized by you, not the other way around'. He sees himself as announcing the coming of another.
Whereas, by contrast, when Jesus talks about John there is not a sort of mutual admiration society of colleagues, still less a kind of a minor admiration for a predecessor. In other words, it is correct to say that John the Baptist does initiate the movement. But to say he is therefore the first Messiah simply goes beyond the evidence."
In addition to Tabor's claims that Jesus had an earthly father and a fellow Messiah, his book also argues it was Jesus' intention to build a dynasty on earth. Tabor says that it was Jesus' half-brother James who would inherit the title role of dynastical king after the crucifixion.
But again, Carson is adamant that the title of the book, "The Jesus Dynasty," is plain wrong.
"The dynasty bit presupposes that there is continuity. That is, there's succession. But the New Treatment evidence, such as it is, is that Jesus is the final king who goes on ruling and reigning. He doesn't need a dynasty, precisely because he is the ongoing king."
Carson insists there was no plan to build a Jesus dynasty.
"No. None," he said. "Jesus was king forever."
The book itself is bound to raise questions and arouse debate. And the argument about the historical Jesus will continue for now.