What does the Bible say about fasting? (what it is + how Jesus taught it)

Q: What does the Bible say about fasting? (what it is + how Jesus taught it)

Fasting is voluntarily going without food (sometimes more) for a time, in order to focus on prayer, humble oneself before God, or seek Him in a time of need or repentance. The Bible never commands a general weekly fast, but it assumes God's people will fast — Jesus said 'when you fast,' not if (). Its purposes in Scripture: - Humbling oneself and repenting — Nineveh fasts at Jonah's warning (); Joel calls Israel to 'return… with fasting' (). - Seeking God in crisis or before a decision — Esther before risking her life (); the church before sending out Paul and Barnabas (; ). - Grief and earnest prayer — David (); Daniel ().

Faith

Short answer

Fasting is voluntarily going without food (sometimes more) for a time, in order to focus on prayer, humble oneself before God, or seek Him in a time of need or repentance. The Bible never commands a general weekly fast, but it assumes God's people will fast, Jesus said 'when you fast,' not if (Matthew 6:16).

Its purposes in Scripture:

Humbling oneself and repenting, Nineveh fasts at Jonah's warning (Jonah 3:5); Joel calls Israel to 'return… with fasting' (Joel 2:12).
Seeking God in crisis or before a decision, Esther before risking her life (Esther 4:16); the church before sending out Paul and Barnabas (Acts 13:2; Acts 13:3).
Grief and earnest prayer, David (2 Samuel 12:16); Daniel (Daniel 9:3).

Question

What does the Bible say about fasting? (what it is, why people fasted, and how Jesus taught it)

Analysis

Fasting in the Bible's story

Fasting runs from Moses' forty days on the mountain (Exodus 34:28) to Jesus' forty days in the wilderness before His ministry (Matthew 4:2). It marks moments of deep dependence: mourning (2 Samuel 12:16), pleading for a nation (Daniel 9:3), corporate repentance (Jonah 3:5; Joel 2:12), and worshipful waiting on God, the prophetess Anna 'worshiped night and day, fasting and praying' (BSB, Luke 2:37), and the early church fasted when commissioning leaders (Acts 13:2; Acts 13:3; Acts 14:23). It is almost always paired with prayer, fasting is not a diet or a hunger-strike to force God's hand, but a way of saying with the body that God matters more than food.

How Jesus taught it

Jesus corrected the way fasting was often done for show. 'When you fast, do not be somber like the hypocrites, for they disfigure their faces to show men they are fasting' (BSB, Matthew 6:16), instead fast quietly, seen by 'your Father, who sees what is done in secret' (BSB, Matthew 6:18). The heart matters more than the appearance. The prophets said the same: God rejects a fast paired with injustice and asks instead for the fast He has chosen, 'to break the chains of wickedness', and one that feeds the hungry (BSB, Isaiah 58:6; Isaiah 58:7). So the Bible's picture is fasting done privately, joined to prayer, and matched by a just and humble life, not a performance.

Sources, trace every one

Every cited verse, in full. Tap any reference to open it in the reader.

Matthew 6:16bsb
When you fast, do not be somber like the hypocrites, for they disfigure their faces to show men they are fasting. Truly I tell you, they already have their full reward.
Jonah 3:5bsb
And the Ninevites believed God. They proclaimed a fast and dressed in sackcloth, from the greatest of them to the least.
Joel 2:12bsb
“Yet even now,” declares the LORD, “return to Me with all your heart, with fasting, weeping, and mourning.”
Esther 4:16bsb
“Go and assemble all the Jews who can be found in Susa, and fast for me. Do not eat or drink for three days, night or day, and I and my maidens will fast as you do. After that, I will go to the king, even though it is against the law. And if I perish, I perish!”
Acts 13:2bsb
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.”
Acts 13:3bsb
And after they had fasted and prayed, they laid their hands on them and sent them off.
2 Samuel 12:16bsb
David pleaded with God for the boy. He fasted and went into his house and spent the night lying in sackcloth on the ground.
Daniel 9:3bsb
So I turned my attention to the Lord God to seek Him by prayer and petition, with fasting, sackcloth, and ashes.
Exodus 34:28bsb
So Moses was there with the LORD forty days and forty nights without eating bread or drinking water. He wrote on the tablets the words of the covenant — the Ten Commandments.
Matthew 4:2bsb
After fasting forty days and forty nights, He was hungry.
Luke 2:37bsb
and then was a widow to the age of eighty-four. She never left the temple, but worshiped night and day, fasting and praying.
Acts 14:23bsb
Paul and Barnabas appointed elders for them in each church, praying and fasting as they entrusted them to the Lord, in whom they had believed.
Matthew 6:18bsb
so that your fasting will not be obvious to men, but only to your Father, who is unseen. And your Father, who sees what is done in secret, will reward you.
Isaiah 58:6bsb
Isn’t this the fast that I have chosen: to break the chains of wickedness, to untie the cords of the yoke, to set the oppressed free and tear off every yoke?
Isaiah 58:7bsb
Isn’t it to share your bread with the hungry, to bring the poor and homeless into your home, to clothe the naked when you see him, and not to turn away from your own flesh and blood?

On contested questions we show every major view, attributed and cited, and pick no winner. Answers are synthesized from primary sources, truth you can trace, not opinion.