6:16-18 Religious fasting is a duty required of the disciples of Christ, but it is not so much a duty itself, as a means to dispose us for other duties. Fasting is the humbling of the soul, Ps 35:13; that is the inside of the duty; let that, therefore, be thy principal care, and as to the outside of it, covet not to let it be seen. God sees in secret, and will reward openly.
16. Moreover, when ye fast—referring, probably, to private and voluntary fasting, which was to be regulated by each individual for himself; though in spirit it would apply to any fast.
be not, as the hypocrites, of a sad countenance: for they disfigure their faces—literally, "make unseen"; very well rendered "disfigure." They went about with a slovenly appearance, and ashes sprinkled on their head.
that they may appear unto men to fast—It was not the deed, but reputation for the deed which they sought; and with this view those hypocrites multiplied their fasts. And are the exhausting fasts of the Church of Rome, and of Romanizing Protestants, free from this taint?
Verily I say unto you, They have their reward.