'Son of Man' in the Bible

I was watching in the night visions, "And with the clouds of the sky one like a son of man was approaching. He went up to the Ancient of Days and was escorted before him.

So he approached the place where I was standing. As he came, I felt terrified and fell flat on the ground. Then he said to me, "Understand, son of man, that the vision pertains to the time of the end."