The disciples were there and they are the one who took the message to the world.
I did not say that the disciples were not up there, but the sermon of the Mount was delivered to a crowd of Jews; not to the disciples only. (Mat. 5:1; 7:28)
John the the Baptist, the last prophet, said that Jesus is the Light and he was sent to be the witness of that Light:
Not John the Babptist but the Hellenist who wrote the gospel of John.
John 1:6 There was a man sent from God, whose name was John. John 1:7 The same came for a witness, to bear witness of the Light, that all men through him might believe. John 1:8 He was not that Light, but was sent to bear witness of that Light.
John was part of that light assigned by the Lord to be light unto the Gentiles. (Isaiah 42:6) Endorsed by Jesus to be the light of the world. (Mat. 5:14)
John 1:9 That was the true Light, which lighteth every man that cometh into the world. John 1:10 He was in the world, and the world was made by him, and the world knew him not. John 1:11 He came unto his own, and his own received him not. John 1:12 But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name:
The true light is Israel as Yahweh said, "Israel is my son." (Exodus 4:22,23)
Because the Jewish religious leaders of that time refused to accept Jesus as the Redeemer, judgment was about to come upon them. We know these things:
Jesus could not have been the redeemer of Israel as Yahweh Himself was the true Redeemer and Savior of Israel. (Isaiah 43:1,3)
The Temple was destroyed, never to be built again at that location.
Watch out! You might get disappointed when the Temple is rebuilt.
The Romans drove the majority of the Jews out of Israel and scattered them throughout the earth.
Of that one, you must be already disappointed that we are back alive and kicking.
Jews lost their ability to maintain their own kind and became a part of Gentile nations. Jews of today are only religious Jews not true descendants of Abraham. Most of Europe has as much Jewish blood in them as any in Israel.
That's where you err for denying reality. We are back and we have not lost our identity. Sorry! I know you don't like that but, what can I do?
The generation that judgment came upon was the generation of Jesus.
I don't think so. unless you have in mind the right person aka Paul.
Today you and I have the same ability to become the children of Abraham, those of faith.
I don't think so because, faith without the Law is as good as a body without the breath of life, aka dead. (James 2:26)
Jesus did not come to destroy the old covenant, but to fulfill it. Mat 5:17 Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.
To fulfill here is the same as to confirm because as long as heaven and earth have not passed away, not a sing law will ever pass away.