Moreover when you fast, be not, as the hypocrites, of a sad countenance: for they disfigure their faces, that they may appear unto men to fast. Verily I say unto you, They have their reward.
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Forasmuch as that prayer which is offered in a humble spirit and contrite heart, shows a mind already strong and disciplined; whereas he who is sunk in self-indulgence cannot have a humble spirit and contrite heart; it is plain that without fasting prayer must be faint and feeble; therefore, when any would pray for any need in which they might be, they joined fasting with prayer, because it is an aid thereof. Accordingly the Lord, after His doctrine respecting prayer, adds doctrine concerning fasting, saying, “When ye fast, benot ye as the hypocrites, of sad countenance.” The Lord knew that vanity may spring from every good thing, and therefore bids us root out the bramble of vain-gloriousness which springs in the good soil, that it choke not the fruit of fasting. For though it cannot be that fasting should not be discovered in any one, yet is it better that fasting should show you, than that you should hew your fasting.
If then he who fasts, and makes himself of sad countenance, is a hypocrite, how much more wicked is he who does not fast, yet assumes a fictitious paleness offace as a token of fasting.