Matthew 6:16-18

16 And when you go without food, be not sad-faced as the false-hearted are. For they go about with changed looks, so that men may see that they are going without food. Truly I say to you, They have their reward.

17 But when you go without food, put oil on your head and make your face clean;

18 So that no one may see that you are going without food, but your Father in secret; and your Father, who sees in secret, will give you your reward.