What was one of the two lines of Old Testament prophecy about?

Les explains that all through the Old Testament there are two parallel lines of prophecy, which he calls like railroad tracks. On one line was a suffering Savior, the promise that one would come who would suffer and die for the sins of Israel. On the other line was the promise of a King and a Kingdom, a glorious Kingdom over which the Son of God Himself would rule and reign, and Israel would be the top dog of the nation. Les points out that when Christ came the first time, Israel wanted the King and the Kingdom, but not the suffering Savior, because dealing with the Savior meant dealing with their sin. They refused to search the Scriptures, so they remained in unbelief, just as the world today wants a utopian kingdom of peace and prosperity but does not want to deal with sin.