Many people asked the religious leaders in Jerusalem if Jesus was the Messiah. Their official response was no, He was doing the miracles by Beelzebub, the prince of the demons. In response Jesus said they had committed the unforgivable sin, because they had rejected Jesus Christ as the Messiah and it is His blood which pays the price so that we can be forgiven of sin. The religious leaders responded to Jesus asking for a sign. He said they would get the sign of Jonah. Yes, that sign includes His death and resurrection, similar to Jonah being in the belly of the beast for three days. But it also included Jonah walking about the city for forty days telling them to repent or else the city would be destroyed. In their case God relented because the people in Nineveh humbled themselves and repented. But in Jerusalem's case Jesus said that because they said they could see and were wise, the sin remained. There was no humbling, there was no repentance. For forty years from the time Jesus told them they had committed the unforgivable sin Jesus and the disciples went through Israel and Jerusalem telling them to repent. Temple records tell us that beginning in 30 AD the atoning sacrifice was never accepted for the next forty years and then in 70 AD the city was destroyed.
The atoning sacrifice involves two goats. One is sacrificed for sin, the other is the scapegoat that becomes an outcast. The Jews were given 40 years to repent, they refused. From that point on they have been outcasts on the earth scattered to the four corners of the earth. God told them in the law of Moses that this is what He would do.
If you remember, when Jesus Christ, the Son of God was crucified He was our atoning sacrifice. At the same time they released a prisoner named Barabbas, meaning son of the father. Barabbas was the scapegoat.
In order for the Jews to be reconciled to God their needs to be an atoning sacrifice. That sacrifice was the Holocaust, meaning "burnt offering". Because they were atoned that is why they were able to return to the land of Israel in 1948.
BTW prophecies in the book of Ezekiel tell us the year that the Jews would be allowed to return. In order to calculate the year you need to know the law of Moses, but it precisely calculates to 1948 being the only year that both Judah and Israel would both be able to return together.