Biblical fasting is going without food, or certain foods, for a set time in order to seek God in prayer. People in Scripture fasted when they grieved, repented, faced danger or needed God’s direction. Jesus expected His followers to fast, but fasting never earns God’s favor. It’s a way of telling God you need Him more than food.
This article is about spiritual fasting, not dieting or intermittent fasting for weight loss. Here’s what the Bible teaches, why Christians fast, the kinds of fasts people practice and how to start wisely.
What is fasting in the Bible?
In Scripture, fasting usually goes hand in hand with prayer. Going without food becomes a way of telling God, with your whole self, that this matters. God’s people fasted:
- In grief. When Nehemiah heard that Jerusalem’s wall was broken down, he “mourned for days, fasting and praying before the God of heaven” (Nehemiah 1:4). Our message Praying for Renewal (Nehemiah 1–2) looks at his prayer.
- In repentance. Through the prophet Joel, God called His people to “return to Me with all your heart, with fasting, weeping, and mourning” (Joel 2:12).
- In danger. Before Queen Esther risked her life by going to the king unsummoned, she asked the Jews of Susa to fast for her for three days (Esther 4:16).
- For protection. Ezra proclaimed a fast to ask God for a safe journey, and “He granted our request” (Ezra 8:21–23).
- When sending people out. The prophets and teachers of the church in Antioch were worshiping and fasting when the Holy Spirit set apart Barnabas and Saul, and they fasted and prayed again before sending them off (Acts 13:1–3).
The Law of Moses set only one regular fast day, the Day of Atonement, when Israel was told, “you shall humble yourselves” (Leviticus 16:29). By the time of Acts, it was known simply as “the Fast” (Acts 27:9). Other fasts in the Bible were voluntary: kept by custom or called in a time of need.
Did Jesus fast?
Yes. After His baptism, the Spirit led Jesus into the wilderness, and Matthew says simply, “After fasting forty days and forty nights, He was hungry” (Matthew 4:2). When the devil tempted Him to turn stones into bread, Jesus answered from Deuteronomy 8:3: “Man shall not live on bread alone, but on every word that comes from the mouth of God” (Matthew 4:4). Our message What Comes After Prayer and Fasting? looks at what His wilderness fast teaches us.
Jesus also taught about fasting in the Sermon on the Mount. Notice that He says when you fast, not if:
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. But when you fast, anoint your head and wash your face, 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.
Matthew 6:16–18 (BSB)
Jesus isn’t against fasting. He’s against fasting for an audience. Our message on Matthew 6:1–18 looks at giving, prayer and fasting done for God alone.
When people asked why His disciples didn’t fast, Jesus said they wouldn’t while He, the bridegroom, was with them: “But the time will come when the bridegroom will be taken from them; then they will fast” (Matthew 9:15). After His ascension, the early church did.
Why do Christians fast?
Not to earn God’s love, impress Him or twist His arm. We are saved by grace through faith, “not by works, so that no one can boast” (Ephesians 2:9). Fasting doesn’t make God owe us anything.
Isaiah 58 shows how fasting can go wrong. The people complained that God ignored their fasts, and God answered that they fasted while mistreating their workers, quarreling and fighting (Isaiah 58:3–4). Then He described the fast He wants:
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 58:6 (BSB)
The next verse adds that it is “to share your bread with the hungry” (Isaiah 58:7). A fast that leaves us harsher, prouder or less generous has missed the point.
So why fast? To humble ourselves before God (Ezra 8:21), to return to Him with our whole heart (Joel 2:12–13), to seek His direction (Acts 13:2–3) and to pray with focus about something heavy. Fasting also shows us what we lean on. Our message Seeking the Kingdom encouraged the church to tie fasting to the worries we carry, and Courageous Faith calls fasting a way of practicing dependence on God with our bodies.
Kinds of fasts
The Bible doesn’t prescribe one method. These are the most common:
- A normal fast: no food, but water. The Gospels mention Jesus’ hunger, not thirst: He “ate nothing during those days” (Luke 4:2).
- A partial fast: giving up certain foods. During three weeks of mourning, Daniel “ate no rich food, no meat or wine” (Daniel 10:3). Today many call this a Daniel fast, often adding Daniel 1:12, where Daniel asked for “only vegetables to eat and water to drink.”
- A one-meal or daytime fast: skipping a meal or two, or fasting until evening, as Israel did in times of grief (Judges 20:26; 2 Samuel 1:12).
- An absolute fast: no food or water, as Esther asked for (Esther 4:16). It was an emergency measure and is dangerous; we don’t recommend going without water.
- A media or technology fast: a modern adaptation, not a fast the Bible describes. Setting aside social media, TV or games for a time can make room for prayer, and it’s a good option for anyone who shouldn’t fast from food.
What is a 21-day fast?
Many churches set aside 21 days of prayer and fasting, often at the start of a year. The number echoes Daniel’s “three full weeks” (Daniel 10:2). Most people don’t go without food for 21 days. They choose a partial fast, skip one meal a day or fast one day a week, and add extra time for prayer.
Clarity Church holds 21 Days of Prayer and Fasting together; that page has a prayer guide and links to outside resources on fasting. Our prayer resources page gathers more, including messages from our 2026 series.
How to fast and pray
- Start small. Skip one meal and spend that time in prayer, or fast from one evening meal to the next. You can build from there.
- Decide ahead of time. Choose your purpose, what you’ll give up and for how long. Write down what you’re praying about.
- Replace, don’t just remove. Use mealtimes to pray and read Scripture, and when hunger hits, let it remind you to pray. Psalm 63, Isaiah 58 and Matthew 6 are good places to start.
- Drink plenty of water. Expect some hunger, tiredness or irritability, especially at first, and be gentle with yourself and others.
- Keep it quiet, not secret. Jesus warns against fasting to be seen, but tell your family so they aren’t surprised, and consider asking a friend to pray with you.
- Break the fast gently. After a day or more without food, start with something small and light rather than a big meal.
- Ask what God showed you. Afterward, notice what you missed most and what you prayed about, and take the next step of obedience.
Who should not fast from food
Fasting is a spiritual practice, not a medical treatment, and fasting from food isn’t right for everyone. This isn’t medical advice: talk with your doctor before fasting from food if you:
- are pregnant or nursing
- have diabetes or another blood-sugar condition
- have a history of an eating disorder
- take medication that must be taken with food, or that affects your blood sugar or blood pressure
- have a chronic illness, are underweight, or are recovering from illness or surgery
Young children shouldn’t fast from food; they can give up a treat or screen time instead. If you’ve struggled with an eating disorder, a non-food fast is the wiser choice. God isn’t measuring how hungry you get: “the LORD sees the heart” (1 Samuel 16:7).
Questions about fasting
The New Testament doesn’t set a schedule or require a particular kind of fast. But Jesus spoke of “when you fast” (Matthew 6:17) and said His followers would fast once He was gone (Matthew 9:15), and the early church fasted before major decisions (Acts 14:23). Christians differ on how often to fast; Scripture leaves that to wisdom and conscience, not rules.
Yes, and you should. Most Christian fasts include water, and the Gospels mention Jesus’ hunger, not thirst (Matthew 4:2). Esther’s fast without food or water was a three-day emergency (Esther 4:16), and Moses’ forty days without bread or water happened in God’s presence on the mountain (Exodus 34:28); neither is a pattern for us. Going without water is dangerous.
There’s no set length. In the Bible, fasts lasted until evening (Judges 20:26), three days (Esther 4:16), three weeks for Daniel’s partial fast (Daniel 10:2–3) and, rarely, forty days (Matthew 4:2). If you’re new to fasting, start with one meal or one day, and talk with your doctor before going without food for longer than that.
Jesus warns against fasting to be noticed; He says to fast so that it shows “only to your Father, who is unseen” (Matthew 6:18). That doesn’t rule out fasting together: God’s people often fasted as a community (Joel 2:15; Acts 13:2). It’s wise to tell your family, and a friend can pray with you. The real question is motive: God or an audience?
Purpose and prayer. A diet aims at your body; biblical fasting aims at God. Skipping lunch to lose weight isn’t a biblical fast, but skipping it to pray can be. Intermittent fasting for health isn’t wrong, but it isn’t what Scripture means by fasting. Fasting without prayer is just going hungry; fasting with prayer tells God you need Him most.
Want to seek God with others? Clarity Church meets Sundays at 10am at Edinbrook Elementary in Brooklyn Park. Plan your visit — come as you are.