He commanded them that they should tell no one the things they had seen, till the Son of Man had risen from the dead.
Why We Lack Understanding
Then a cloud overshadowed them, and a voice from the cloud said, “This is my dearly loved Son. Listen to him.” Suddenly, when they looked around, Moses and Elijah were gone, and they saw only Jesus with them. As they went back down the mountain, he told them not to tell anyone what they had seen until the Son of Man had risen from the dead. So they kept it to themselves, but they often asked each other what he meant by “rising from the dead.”
Then they asked him, “Why do the teachers of religious law insist that Elijah must return before the Messiah comes?” Jesus responded, “Elijah is indeed coming first to get everything ready. Yet why do the Scriptures say that the Son of Man must suffer greatly and be treated with utter contempt? But I tell you, Elijah has already come, and they chose to abuse him, just as the Scriptures predicted.”
Once you grow and develop the right condition inwardly, the words which Jesus spoke become so clear that you are amazed that you did not grasp them before. Our Lord doesn’t hide these things from us, but we are not prepared to receive them until we are in the right condition in our spiritual life.