Fasting in the Bible (Matthew 6)

Fasting in the Old Testament

While the Day of Atonement was the only required day of fasting in the Old Testament, there were occasions throughout the year for voluntary fasting. Rather than avoiding specific foods, fasting usually involved abstinence from all foods for a predetermined period of time. It was always accompanied by prayer and was used to express grief, penitence or humble devotion to God. Fasting was encouraged at times of national crisis as an indication that Israel or Judah was wholeheartedly dedicated to the Lord (Judges 20:26, Joel 1:14). Individuals in particular distress also fasted (1 Samuel 1:7, 2 Samuel 12:22). The duration of a given fast ranged from several hours to as long as 40 days. After the exile there were at least four commonly practiced periods of fasting (Zecheriah 8:19). For example, a tradition began of fasting on the ninth of Ab (the fifth month, spanning our July and August). This fast was intended to commemorate the destruction of the Jerusalem temple, and it became customary to read Lamentations on that day.

Fasting in pagan religion

Fasting was also practiced in some forms of Greek pagan religion. One of the initiatory rites of the Eleusinian mystery religion involved a fast, and the cults of Isis and Cybele also entailed some fasting. Abstinence from food, as well as sexual abstinence, was often thought to be necessary preparation before undergoing a ritual. The Greeks rarely practiced lengthy fasts, but many cults had a number of taboos involving food (the Pythagoreans, e.g., were vegetarian).

Fasting in the New Testament and the church

Fasting remained common throughout the New Testament era. The Pharisees fasted twice a week, on Mondays and Thursdays (Luke 18:12). Jesus, the disciples of John the Baptist and Paul practiced substantial fasts as well. Matthew 6:16-18 indicates that fasting remains a legitimate form of worship for Christians. During the first few centuries of the Christian church a theology of asceticism with heroic acts of prolonged fasting arose. But Jesus’ words also provide a reminder that true fasting is directed toward God, not toward impressing others. Like the prophets before Him (Isaiah 58:1-12, Jeremiah 14:10-12, Zecheriah 7), Jesus proclaimed that true fasting is an indication of the heart’s inclination towards God.