That you appear not unto men to fast, but unto your Father who is in secret: and your Father, who sees in secret, shall reward you openly.
All Commentaries on Matthew 6:18 Go To Matthew 6
John Chrysostom
AD 407
Also if He bade us not to be of sad countenance that we might not seem to mento fast, yet if anointing of the head and washing of the face are always observed in fasting, they will become tokens of fasting.
Therefore the simple interpretation of this is, that is added as an hyperbolical explanation of the command; as though He had said, Yea, so far shouldye be from any display of your fasting, that if it might be (which yet it may not be) so done, ye should even do such things as are tokens of luxury and feasting.
Hom. xx: In almsgiving indeed, He did not say simply, ‘Do not your alms before men,’ but added, ‘to be seen of them.’ But in fasting and prayer He added nothing of this sort; because alms cannot be so done as to be altogether hid, fasting and prayer can be so done. The contempt of men’s praise is no small fruit, for thereby we are freed from the heavy slavery of human opinions, and become properly workers of virtue, loving it for itself and not for others. Foras we esteem it an affront if we are loved not for ourselves but for others 'sake, so ought we not to follow virtue on the account of these men, nor to obey God for men’s sake but for His own.
Spiritually interpreted - the face may be understood to mean the mental conscience. And as in the eyes of man a fair face has grace, so in the eyes of God a pure conscience has favour. This face the hypocrites, fasting on man's account, disfigure, seeking thereby to cheat both God and man; for the conscience of the sinner is always wounded. If then you have cast out all wickedness from your heart, you have washed your conscience, and fast well.
Spiritually again, “thy head” denotes Christ. Give the thirsty drink and feed the hungry, and therein you have anointed your head, that is, Christ, who cries out in the Gospel, “In that ye have done this to one of the least of these my brethren, ye have done it to me.” .
And truly we ought to wash our face, but to anoint, and not to wash, our head. For as long as we are in the body, our conscience is foul with sin. But Christ who is our head has done no sin.