And of the mortification of the flesh and discipline of the body we thus teach, just as the Confession states, that a true and not a feigned mortification occurs through the cross and afflictions by which God exercises us [when God breaks our will, inflicts the cross and trouble]. In these we must obey God's will, as Paul says, Rom. 12, 1: Present your bodies a living sacrifice. And these are the spiritual exercises of fear and faith. But in addition to this mortification which occurs through the cross [which does not depend upon our will] there is also a voluntary kind of exercise necessary, of which Christ says Luke 21, 34: Take heed to yourselves lest at any time your hearts be overcharged with surfeiting. And Paul, 1 Cor. 9, 27: I keep under my body, and bring it into subjection, etc. And these exercises are to be undertaken not because they are services that justify, but in order to curb the flesh, lest satiety may overpower us, and render us secure and indifferent, the result of which is that men indulge and obey the dispositions of the flesh. This diligence ought to be perpetual, because it has the perpetual command of God. And this prescribed form of certain meats and times does nothing [as experience shows] towards curbing the flesh. For it is more luxurious and sumptuous than other feasts [for they were at greater expense, and practised greater gluttony with fish and various Lenten meats than when the fasts were not observed], and not even the adversaries observe the form given in the canons.