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Faith & Spiritual Life

What Does the Bible Say About Fasting?

Fasting is a spiritual discipline woven throughout both Testaments. Moses, David, Elijah, Esther, Daniel, and Jesus all fasted. In the Sermon on the Mount, Jesus said 'when you fast' — not 'if you fast' — assuming it as a normal practice. Isaiah 58 gives the most complete biblical theology of fasting, distinguishing true fasting from empty ritual.

Key Bible Verses

"When you fast, do not look somber as the hypocrites do, for they disfigure their faces to show others they are fasting… But when you fast, put oil on your head and wash your face."

Matthew 6:16–17Study this verse

"Is not this the kind of fasting I have chosen: to loose the chains of injustice and untie the cords of the yoke, to set the oppressed free and break every yoke?"

Isaiah 58:6Study this verse

"While they were worshiping the Lord and fasting, the Holy Spirit said, 'Set apart for me Barnabas and Saul for the work to which I have called them.' So after they had fasted and prayed, they placed their hands on them and sent them off."

Acts 13:2–3Study this verse

"Even now, declares the Lord, return to me with all your heart, with fasting and weeping and mourning."

"After fasting forty days and forty nights, he was hungry."

Matthew 4:2Study this verse

Common Questions

Why do Christians fast according to the Bible?

Scripture shows fasting done for several reasons: seeking God's guidance (Acts 13:2–3), mourning and repentance (Joel 2:12), interceding for others (Esther 4:16), and spiritual warfare (Matthew 17:21 in some manuscripts). The common thread is humbling oneself before God and expressing dependence on him rather than physical sustenance.

How long should a fast be according to the Bible?

The Bible records fasts of one day (Judges 20:26), three days (Esther 4:16), seven days (1 Samuel 31:13), twenty-one days (Daniel 10:3), and forty days (Moses in Exodus 34:28, Elijah in 1 Kings 19:8, and Jesus in Matthew 4:2). Scripture does not prescribe a standard length.

What is the difference between a full fast and a partial fast?

A full fast involves abstaining from all food (and sometimes water, as in Esther 4:16). A partial fast, like Daniel's in Daniel 10:3 ('no choice food, no meat or wine'), involves restricting certain foods. Both are biblical; the type of fast should be chosen prayerfully and with wisdom about one's health.

Explore Scripture Deeper

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