Jesus said there are some standing here that will not die till all these things be fulfilled. At that time they showed Him the beautiful temple but He said that not one stone will be left on another. And when it happened forty years later, some of them were still alive. They were in dire straits and the famine in Jerusalem was so severe that some even ate their children. The Romans slaughtered the Jews so that it's a miracle that any Jew survived that generation. About the sun and moon turning dark. When Jesus hang on the cross there was total darkness from noon till 3pm, for three hours. Daniel said in the end times knowledge will increase, and we know how knowledge increased in our time.