Popular 21-day fast ideas include the Daniel Fast (vegetables, fruit, whole grains and water), skipping one meal a day, giving up sugar, coffee or alcohol, and non-food fasts from social media, streaming, video games, news or your phone in the morning. Choose something that costs you and give that space to prayer. For a phone fast, a prayer lock app like Prayer Latch can keep those apps closed until you pray.
Many churches begin the year with 21 days of prayer and fasting, following Daniel's three-week fast in Daniel 10. A fast isn't a diet or a way to earn God's favour. It's choosing to go without something good so that you feel your need for God more, and turn that hunger into prayer. For a phone fast, Prayer Latch, a Christian app blocker, keeps the apps you give up locked each morning until you've prayed. Scripture quotations are from the King James Version, which is in the public domain.
"In those days I Daniel was mourning three full weeks. I ate no pleasant bread, neither came flesh nor wine in my mouth, neither did I anoint myself at all, till three whole weeks were fulfilled." Daniel 10:2–3
Why 21 days?
Daniel fasted for "three full weeks" while he sought understanding from God (Daniel 10:2–3). Three weeks is also long enough to feel the cost and short enough to finish, which is why many churches choose it for a January season of prayer.
Food fast ideas
- The Daniel Fast: vegetables, fruit, whole grains, legumes, nuts and water, with no meat, dairy, sugar, bread made with yeast or caffeine. See the Daniel Fast guide.
- One meal a day (skip breakfast and lunch, or lunch and dinner).
- Sunrise to sunset: no food during daylight, water allowed.
- No sugar or desserts.
- No caffeine.
- No alcohol.
- No meat.
- No eating out or takeout, giving the money saved away.
- No snacking between meals.
- Liquids only for one day a week (only with your doctor's OK).
Non-food fast ideas
- All social media.
- Social media until after morning prayer.
- Your phone for the first hour of the day.
- TikTok, Reels and YouTube Shorts.
- Streaming shows and movies.
- Video games.
- News apps, apart from one set time a day.
- Podcasts and music in the car.
- Online shopping.
- The snooze button.
- Phones in the bedroom.
- Complaining.
- Staying up late.
- Dating apps.
- Sports scores and fantasy apps.
Prayer Latch tip: Pick your non-food fast from the list above, then choose just those apps in Prayer Latch's Lock list and set the lock time to when you wake. For all 21 days, every reach for them starts with a prayer instead.
Can I fast from something other than food?
Yes. In Scripture fasting usually means food, and food fasts remain the classic practice. But the purpose of fasting, going without in order to seek God, applies to anything that holds too much of your heart. Many people who can't fast from food for medical reasons fast from media instead. Paul's question fits: "All things are lawful unto me, but all things are not expedient: all things are lawful for me, but I will not be brought under the power of any" (1 Corinthians 6:12, KJV).
How do I plan a 21-day fast?
- Choose your fast, and write it down with clear rules: what's out, what's allowed, any exceptions.
- Choose your focus. What are you seeking God about? Write two or three prayer requests.
- Choose your replacement. Decide what fills the time or the hunger: a Bible reading plan, a prayer time, worship music.
- Tell someone, or fast with your church or a friend.
- Check your health. If you're pregnant, diabetic, on medication or have a history of eating disorders, talk to your doctor before any food fast, and choose a non-food fast instead if needed.
What should I pray during a fast?
Each time you feel the hunger or reach for what you've given up, turn it into a short prayer. Jesus answered his own hunger in the wilderness with Scripture: "Man shall not live by bread alone, but by every word that proceedeth out of the mouth of God" (Matthew 4:4, KJV). Pray for your requests, for your church, and simply to know God more.
What should I not do while fasting?
Make a show of it. "But thou, when thou fastest, anoint thine head, and wash thy face; That thou appear not unto men to fast, but unto thy Father which is in secret" (Matthew 6:17–18, KJV). Fasting together as a church is fine; announcing your sacrifice for admiration isn't.
How can I keep a phone fast for 21 days?
Lock the apps rather than relying on willpower each morning. Prayer Latch locks the apps you choose at your wake-up time and at any other lock times you add. When you reach for one, it asks you to pray first, so every urge to scroll becomes a reminder to pray, which is the whole point of a fast. Its first 7 days are free, and an emergency unlock is always there for real needs.
Pray before you scroll
Prayer Latch locks your chosen apps each morning until you pray. Your first 7 days are free, no card needed.
Updated October 27, 2026 by the Prayer Latch team at Janus Works LLC.