Matthew 6:16

Moreover, when ye fast, &c.— Our Lord goes on to apply the general advice, before given, to private fasting as well as to private prayer. The Greek word σκυθρωπος properly denotes a fretful and angry countenance; but here it signifies a "face disfigured with mortification and fasting." The LXX have used the same word, Genesis 40:7 to express a sad countenance. See also Proverbs 15:13. This word, as well as 'Υποκριται, hypocrites, refers to the theatre, and to those actors and dissemblers there, who put on every countenance to serve their purpose. The word αφανιζουσι, rendered they disfigure, signifies to cause to disappear, or vanish, or to destroy; and is the same word which has been rendered, in the 19th and 20th verses, corrupt. These hypocritical actors wonderfully affected the fame of extraordinary holiness. Hence they assumed very austere countenances in their fasts; they put on the appearance and dress of mourners, and induced a kind of paleness, at least as much as they could, over their countenance. In short, they made their natural face to disappear, as much as possible; putting on an artificial one, as the players of old were wont to put on their masks. See Fortuita Sacra, p. 14. Our Saviour refers here more particularly to the private and voluntary fasting of the Pharisees: they fasted on Mondays and Thursdays; but those who would be thought more devout than the rest, fasted besides on Tuesdays and Fridays, and abstained from all kind of food till sun-setting. There can be no doubt that our Saviour speaks here of private fasting only; because, when public sins and calamities are to be mourned for, it ought to be performed in the most public manner. Doddridge renders this, When you keep a fast, be not like the hypocrites, putting on a dismal air; for they deform their countenances, that, &c.