Apostolic Fathers: Didache
Excursus on Fasting
Fasting is an intentional abstinence from food, drink or activity as a spiritual exercise to humble yourself before God so that you can receive His gifts. Fasting was done by both Jews and Christians. The Greek and Roman philosophers never encouraged fasting. However, they believed in a notion of a Utopian existence where food and drink were no longer necessary.
Christians may fast in many ways. You may abstain from a favorite food, a beloved activity or a harmful habit. This sacrifice is designed to humble your soul before God (Psalm 35:13; 69:10; Daniel 10:12; Zechariah 7:5). Proper fasting does not include abstaining from something you despise. It can be a total fast with no food or a simple fast with a handful of items being withheld.
Fasting is usually done for three reasons: (1) mourning the death of a loved one, (2) repentance over sin, and (3) preparation for entering into a deeper relationship with God. Each reason has a different source. Mourning is centered in grief. Repentance is centered in sorrow. Preparation is centered in wonder.
Fasting for mourning is found throughout the Old Testament (Judges 20:26; 1 Samuel 31:13; Daniel 10:2-3). Many times, Israel fasted over the death of the ruling king or a prophet. Esther and Mordecai, along with all the Jews in Susa, fasted after Haman published his annihilation edict. This led to the establishment of the annual Purim fast (Esther 4:3, 16; 9:31).
Fasting for repentance over sins is the result of the Law's crushing of the sinful heart. Nineveh fasted after Jonah preached their impending destruction (Jonah 3:5-9). Nehemiah and Daniel fasted over the exiles returning to Jerusalem (Nehemiah 1:4; Daniel 9:3). The returning exiles in Jerusalem fasted after Ezra read the Law to them, acknowledging their sinfulness (Ezra 8:23; Nehemiah 9:1).
Fasting in preparation for enlightenment is also found often in the Bible. Moses spent forty days on Mount Sinai fasting before he received the Torah (Exodus 34:28; Deuteronomy 9:9). Daniel fasted before receiving the apocalyptic visions of the latter half of his prophecy (9:3; 10:2, 12). Cornelius received his vision to call Peter while he was fasting as he prayed to God (Acts 10:30). The church in Antioch fasted while they ministered. During one of these fasts, the Holy Spirit called for Paul and Barnabas to be separated for missionary work (Acts 13:2-3).
This preparation is referenced by the Teaching with regard to Baptism. Those who are about to be baptized are encouraged to fast. The baptizing minister and as many of the congregation as are able are also encouraged to fast (7:4). This fasting before initiation into the Christian Church culminated in the first reception of the Lord's Body and Blood in the Lord's Supper. This is evident especially from the practice of Baptism and Confirmation during the Easter Vigil service. The catechumens were taken from the Service of the Word, which constitutes much of the Vigil service, and taken into the place of Baptism. When they were baptized, they went straight from the baptismal font to the altar as the Lord's Supper was being consecrated on Easter morning.
The Lenten season of fasting also comes to us as a manner of preparation for spiritual warfare. The Lenten fast is modeled after the forty days Jesus fasted in the Wilderness before Satan's temptations (Matthew 4:2; Mark 1:12; Luke 4:2). In this life, Christians are constantly undergoing battles with the evil spirits and desires of this age. As Israel fasted before going into a physical battle (1 Samuel 7:6; 2 Chronicles 20:3), the Christian should fast in order to be prepared for the spiritual battle with sin, death and the devil.
These situations for fasting are encouragements for the faithful. Only one fast was commanded in the Bible. The fast of the Day of Atonement, Yom Kippur (Leviticus 16:29-34; 23:36-32; Numbers 29:7). Other days were added in post-exilic Judaism for the remembrance of Babylon's destruction of Jerusalem (Zechariah 7:1-7; 8:19). This commandment gives the impetus for Jesus to speak about fasting as an activity that a Christian will do: “when you fast” (Matthew 6:16).
Just as God instituted four additional post-exilic fast days through Zechariah, the zealous among the Jews in the intertestamental period added two days a week (Teaching 8:1; Luke 18:12). The Teaching takes the hypocrites' fast days and encourages those who wish to continue this pious exercise to move it from Monday and Thursday to Wednesday and Friday (8:1).
While the Teaching taught fasting, the contemporary New Testament epistles say nothing about fasting. Without examples of this, many believe that fasting didn't arise for Greek congregations. The Greek world did not see a benefit in fasting.
However, the Jewish background of the Church becomes prevalent again after the Apostolic Age. Teaching 8:1 lists Wednesday and Friday as the proper days of fasting. During Holy Week, Jesus did not enter Jerusalem on Wednesday. He was presumably fasting. He was crucified on Friday. Therefore the Christian remembers the suffering and Passion of our Lord Jesus Christ while they fast. This becomes important especially as Irenaeus discusses the Easter fast, where Christians were encouraged to fast for the entire time between the Good Friday service and Easter Sunrise services. The Apostolic Constitutions (written 375-380 AD) describe this great fast coming from the evening of Maundy Thursday until Easter Sunrise (V 19).
The exercise of fasting is not simply an individual exercise. It is primarily a communal exercise. God commanded all Israelites to fast on the Day of Atonement. The post-exilic fasts were encouraged upon all Jews. Fasting in these circumstances leads to the encouragement of faith in the entire community. Christians come together better in this moment of sacrifice and fasting. This gives the opportunity for the Holy Spirit to work within the community. The Christians at Antioch fasted when Paul and Barnabas were called to become missionaries (Acts 13:2-3). Jeremiah charges Baruch to read the words of the Lord on a fast day (36:6, 9; see also Baruch 1:14; 2 Baruch 86). Fasting from worldly things leads us closer to spiritual things.
While fasting is a profitable exercise, it falls under the realm of Christian freedom. There are no fasts that a Christian must observe. The season of Lent has been historically set aside, by the consensus of the Church, as a time of fasting and prayer to prepare Christians for Easter. Christian fasting is a matter of Christian freedom: “One person esteems one day as better than another, while another esteems all days alike. Each one should be fully convinced in his own mind. The one who observes the day, observes it in honor of the Lord. The one who eats, eats in honor of the Lord, since he gives thanks to God, while the one who abstains, abstains in honor of the Lord and gives thanks to God. For none of us lives to himself, and none of us dies to himself. For if we live, we live to the Lord, and if we die, we die to the Lord. So then, whether we live or whether we die, we are the Lord's” (Romans 14:5-8).
So, Christian, do you have to fast? No. Fasting is optional. However, freedom in the Gospel should never lead us to throw away what can be profitable.