Matthew 6:16 (ESV)

16 “And when you fast, do not look gloomy like the hypocrites, for they disfigure their faces that their fasting may be seen by others. Truly, I say to you, they have received their reward.

Fasting is the practice of going without food for a period of time, typically a day (sunset to sunset).1 It was done for a number of reasons, including confession of and sorrow for sin (Leviticus 16:29–34), lamentation over national troubles or threats (Judges 20:26), or in response to sad tidings (Nehemiah 1:4).2 At its heart, it served as a reminder that God is more important than basic human needs. It was a common practice in Judaism.3