As Christ compareth the understanding of scripture to a key, so compareth he it to a net, and unto leaven, and unto many other things for certain properties. I marvel, therefore, that they boast not themselves of their net and leaven, as well as of their keys; for they are all one thing. But as Christ biddeth us beware of the leaven of the Pharisees, so beware of their counterfeited keys, and of their false net; which are their traditions and ceremonies, their hypocrisy and false doctrine, wherewith they catch, not souls unto Christ, but authority and riches unto themselves.

The Obedience of A Christian Man (1528)