Mocking Popery ≠ Christianity

To say that men may lawfully eat flesh on a Friday, and to mock all the superstitions of popery, and to say that they are but empty and trivial things -- that they can do with ease. But, at the same time, if a man asks them what it is to be regenerate, what patience is, what newness of life is, and what it is to be fashioned again after the image of God -- there the majority of them will show that they never tasted the truth of the gospel, but have disregarded all but the externals, and never came to the real substance of it.

~John Calvin, The Twenty-Ninth Sermon on Ephesians.