Understanding Matthew 17:21 – The Power of Prayer and Fasting

Matthew 17:21: “This kind goeth not out but by prayer and fasting.”

What does Jesus mean by “this kind”? He is referring to a particular level of spiritual resistance—whether it be sickness, demonic oppression, or deeply rooted issues—that does not yield to prayer alone but requires both prayer and fasting.

Jesus teaches that some breakthroughs require a deeper level of commitment. If a sickness, affliction, or demonic presence does not respond to simple prayer, it does not mean God is unwilling to help—it means that a greater level of faith and spiritual discipline is needed to overcome it. Jesus is providing a formula for victory: when ordinary prayer seems ineffective, fasting with prayer is the key.

The Bible clearly connects sickness, disease, and suffering with the curse of the law (Deuteronomy 28). In this chapter, God lists diseases as part of the punishments for disobedience. However, the Good News is found in Galatians 3:13:

“Christ hath redeemed us from the curse of the law, being made a curse for us.”

This means that Jesus took the punishment for sin and sickness upon Himself so that we could be set free. His sacrifice on the cross not only brings salvation for the soul, but also healing for the body. Salvation and divine healing are inseparable, like two links in the same chain. If God can save a lost soul, He can heal a sick body.

Healing is Part of the Atonement

Isaiah 53:5 says: “He was wounded for our transgressions. He was bruised for our iniquities: the chastisement of our peace was upon him; and with his stripes we are healed.”

The suffering of Jesus was not just for our sins, but also for our healing. 

 Fasting and prayer help us focus on this truth, allowing us to receive healing more fully.

Hebrews 13:8 declares: “Jesus Christ the same yesterday, and today, and forever.”

This means that if Jesus healed the sick while on earth, He still heals today. His power did not end with the apostles—His promises remain for all who believe.

Mark 16:17-18 confirms this: “These signs shall follow them that believe… they shall lay hands on the sick, and they shall recover.”

Notice that Jesus did not say healing was only for the early church or just for the apostles. He said it was for those who believe—which includes us today.

The reason many people do not see these miracles is not because God has changed, but because many have stopped believing. Jesus said, “These signs shall follow them that believe.” If the signs are not following, the issue is not with God—it is with our level of belief.

This is where fasting comes in.

If someone struggles with doubt or unbelief, Jesus’ solution is clear:
Fast and pray, and you will develop the faith needed to receive healing and breakthrough.

Fasting helps us:

• Eliminate distractions that weaken our faith
• Draw closer to God, increasing our spiritual strength
• Overcome doubt, making room for supernatural faith

When faith is too weak, fasting strengthens it. This is why Jesus instructed His disciples in Matthew 17:21 that certain miracles require both prayer and fasting.

Many people today assume that God intended for us to rely on doctors and medicine instead of divine healing. But if this were true, we would have to ask:

1. Which school of medicine should we trust? Medicine is constantly changing—what doctors recommend today, they may reject tomorrow.
2. Does God favor the rich over the poor? If healing only comes through medical treatment, then only those who can afford doctors would have access to healing. But God’s healing power is available to all, regardless of wealth.
3. Why would Jesus heal all who came to Him if sickness was part of God’s plan? If sickness was truly God’s will, then Jesus would have been working against God’s plan by healing the sick. But He healed everyone who came to Him in faith.

This does not mean the medical profession is sinful—medicine has its place and is a wonderful gift of God’s grace to mankind, especially for those who do not yet have faith for healing. There is no argument against the important role of doctors and medicine.  The argument is against exalting these as the highest possible solution.  They are limited. Gods’ power is not. For those who are able to build faith to believe, divine healing offers a higher way.

1. Some problems require more than just prayer—they require fasting.
2. Sickness is not from God—it is part of the curse, but Jesus has redeemed us from it.
3. Healing is available to all who believe.
4. Fasting strengthens faith, making miracles possible.
5. Divine healing is for today—Jesus has not changed.

If you or someone you know is struggling with sickness, consider fasting and prayer. Jesus’ words still hold true:

“This kind goeth not out but by prayer and fasting.” (Matthew 17:21)

Fasting is not just about denying food—it is about feeding your faith. When faith reaches the level Jesus requires, healing, deliverance, and miracles will follow.