Why did God disperse Israel and take away the temple?
God dispersed Israel and took away the temple because they kept rejecting the Old Testament promises of the King and Kingdom, rejected their Messiah, and rejected their King. After Pentecost their spiritual decline led to A.D. 70, when God sovereignly permitted Rome under Titus to destroy Jerusalem and the temple, uprooting them into dispersion.
Les teaches that Israel, after the crucifixion and Pentecost, continued to reject the offers of the Old Testament promises of the King and the Kingdom, along with her role to be the evangelist to the pagan world. Because of this, Israel went down spiritually. Finally in A.D. 70, forty years after Pentecost, God sovereignly permitted the Roman army under Titus to destroy the temple and Jerusalem and to uproot the Jew from the Promised Land into the dispersion that continues to this day. It was all because they rejected the promises, their Messiah, and their King. So God dispersed them, took away their temple and religion, and turned to the Gentile with the Age of Grace. Les also notes that God deals in specific prophetic time frames, such as Daniel's 490 years, with 483 consummated and then a break, picking up the final seven years in Daniel 9:27.