17 But you, when you fast, anoint your head, and wash your face; 18so that you are not seen by men to be fasting, but by your Father who is in secret, and your Father, who sees in secret, will reward you.
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, Psalm 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.
Matthew Henry's Commentary on Matthew 6:17-18
Commentary on Matthew 6:16-18
(Read Matthew 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, Psalm 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.