I. Old Testament

A. The only fast commanded by God was the Day of Atonement (Leviticus 16:29-31; 23:26-32; Numbers 29:7)
B. Other reasons for fasting can be observed: war (Judges 20:26; 1 Samuel 7:6); danger (Ezra 8:21-23; Esther 4:16); illness (2 Samuel 12:16-23); death (1 Samuel 31:13; 2 Samuel 1:12); forgiveness (1 Kings 21:17-29; Jonah 3:4-10; Nehemiah 9:1-3)
C. Just as reasons varied, so did lengths of fasts – from one day (Judges 20:26) to seven days (1 Samuel 31:13)

II. New Testament

A. Many fasted for ritualism (Luke 18:12) and show (Matthew 6:16)
B. Reasons for proper fasts in the New Testament: ministry (Matthew 4:1-11; 2 Corinthians 6:4-10; 11:23-28); sending out missionaries (Acts 13:1-3); appointment of elders (Acts 14:21-23)

III. What about today?

A. Jesus expects His disciples to fast (Matthew 6:16-17)
B. First century Christians practiced fasting (Acts 13:1-3; 14:21-23; 2 Corinthians 6:4-10; 11:23-28)
C. Fasting should be done to help us focus on a specific spiritual purpose