The reply from Jesus surprised the disciples. The great temple complex, which seemed to show strength, permanence, and God’s favor toward the Jewish people, would be completely destroyed.
Not one stone here will be left on another: The words of Jesus emphasized the total destruction that would come through the Roman army’s attack on the temple complex (Josephus, Antiquities 6.9.1; 7.1.1.).
Some people argue that the prophecy was not fulfilled because a few foundation stones still remain. But this misunderstands prophetic language. A prophet would not normally speak in exact percentages or technical detail. Anyone who saw Jerusalem after AD 70 would have understood that the prophecy of Jesus had come true.