He was despised and rejected by men, a man of sorrows and acquainted with grief. And as one from whom men hide their face, he was despised, and we didn't respect him. And a lot of the prophecies, like Daniel 7.14 for instance, explain that when the Messiah comes there will be this awesome new everlasting kingdom. And that had to sound pretty good to people who'd had their autonomy taken away from them. So some religious Jews saw Jesus in those prophecies and came to believe, either during his life or shortly thereafter, that he was the Messiah. Most of them thought the new everlasting kingdom was right around the corner, which is probably why no one bothered to write down much about the life of Jesus for several decades, by which time it was clear that we might have to wait a bit for this brilliant new everlasting kingdom. I should note, by the way, that the idea of a Messiah was not unique to the Jews at the time.