But the high priest rose up, and all who were with him (that is, the party of the Sadducees), and filled with jealousy...
Acts 5:17

Pride is a great motivator of evil. The high priest and the Sadducees were driven to jealousy and disbelief by their pride, so they "rose up" against Peter and the other apostles. The evidence of God provided by great miracles requires ever greater pride to ignore, but pride and fear are both like faith: The more you exercise them, the stronger they get.

The priests and Sadducees were afraid and jealous of the power of God manifested in the Apostles, but were even more afraid and jealous of the influence the Apostles had over the people. They cared more about their power than about the truth or the Kingdom of God.