For he knew that the chief priests had delivered him for envy.
Note 6 at Mr 15:10: The chief priests had deceived themselves and other religious people into believing that they were condemning Jesus for godly reasons, but even an ungodly ruler like Pilate could see through their lies. Religious bondage blinds people to truth even more than sin.
The true motivation behind the chief priests and scribes' actions was just envy. They were doing all of their religious works to be seen of people (Mt 23:5), and Jesus was getting more recognition than they were.
The same thing is true of persecution today. All strife is rooted in pride (Pr 13:10).