We’re prone to think of fasting in negative terms. It’s understandable. Fasting is abstaining. It’s going without food and drink, or some other otherwise good gift from God. Perhaps the reason so many of us fast so infrequently is because we think of fasting mainly as what we’re going without rather than what we’re getting.

But Christian fasting is not only going without. It is not simply abstaining. The goal of Christian fasting, in fact, is not going without but getting. Our abstaining always serves some greater end and purpose — some eventual gain, not loss. Christian fasting is abstaining for the sake of some specific Christian purpose, or it is not truly Christian.

Jesus did not waffle as to whether his church would fast. “When you fast,” he said — not “if” (Matthew 6:16–17). “They will fast,” he promised (Matthew 9:15). And so the early church fasted (Acts 9:9; 13:2; 14:23), and for two millennia Christians have fasted. And when we have done so in truly a Christian way, the end result has not been loss but gain. But in order for Christian fasting to become a spiritual feast, we have to rehearse its purpose and benefits.

Purpose in (Christian) Fasting

Fasting is freshly fashionable in many quarters today — which means Christians need to be all the more careful to take our cues on this subject from Jesus, and not popular culture. Just a generation ago, a growing number of voices were claiming that fasting is bad for your health. Now it’s flipped. Today, more and more dieticians are preaching, “When done correctly, fasting can have beneficial physical effects” (Celebration of Discipline, 48). But what’s the difference between fashionable fasting and Christian fasting?

The key difference is Christian purpose. We could say Spiritual purpose — with a capital S for the Holy Spirit. Not just spiritual as opposed to material, but Spiritual as opposed to natural. For Christians, an essential, irreducible aspect of Christian fasting is a Christian purpose. Whether it’s strengthening earnest prayer (Ezra 8:23; Joel 2:12; Acts 13:3). Or seeking God’s guidance (Judges 20:26; Acts 14:23) or his deliverance or protection (2 Chronicles 20:3–4; Ezra 8:21–23). Or humbling ourselves before him (1 Kings 21:27–29; Psalm 35:13). Or expressing repentance (1 Samuel 7:6; Jonah 3:5–8) or grief (1 Samuel 31:13; 2 Samuel 1:11–12) or concern for his work (Nehemiah 1:3–4; Daniel 9:3). Or overcoming temptation and dedicating ourselves to him (Matthew 4:1–11). Or best of all, expressing love and devotion to him (Luke 2:37), and saying with our fast, “This much, O God, I want more of you.”

Without a Spiritual purpose, it’s not Christian fasting. It’s just going hungry.

Benefits of (Christian) Fasting

Christians might fast for dietary reasons and for the various physical benefits nutritionists now highlight. But dietary goals aren’t what make fasting Christian. Rather, what Spiritual fruit might we receive from God in response to our purposeful Christian fasting? How does God reward faith-filled fasting?

That Christian fasting is rewarding is plain, in the words of Christ himself, in a very prominent place. In the Sermon on the Mount, Jesus exhorts us to fast in secret, not for show, with the promise that “your Father who sees in secret will reward you” (Matthew 6:18). God rewards fasting. But how?

First, a vital clarification. The fasting God rewards is not a declaration of our strength of will, but an expression of our emptiness, longing to be filled by him. Christian fasting doesn’t come from our own power, but from a heart that God himself works in us (Philippians 2:12–13) and strength that God himself supplies (1 Peter 4:11).

Realizing this is not about our strength or willpower, what are the rewards he gives, through his free and unconstrained grace, when we fast for his eyes, and not as a show for others?

1. Answers to Earnest Prayer

The first and most immediate answer is the reward of what our fast is for. What was the specific stated purpose as we rehearsed above? Fasting functions as a kind of assistant to prayer. It comes alongside some specific request we’re making of God, through the access we have in Christ (Romans 5:2; Ephesians 2:18; 3:12), and expresses an unusual earnestness. Fasting, as a handmaid of prayer, makes some special plea to God, with an added intensity from normal, everyday prayer.

Fasting is a kind of special measure in the life of faith. Normal life is not fasting. Normal life is steady-state prayer and enjoying the Giver through his gifts of food and drink. Fasting is a special mode, for unusual prayer and for showing the Giver we enjoy him more than his gifts.

2. More of God Himself

This leads, then, to the ultimate reward of Christian fasting, and the “best of all” purposes we highlighted above: God himself. More important than God’s earthly guidance and protection and deliverance and provision is our eternal reception of and rejoicing in him.

God made us eaters and drinkers to teach us about himself. He made our world edible and drinkable so that we might better taste his goodness when our mouths are full, and rehearse that he is better than food and drink when our stomachs are empty. Fasting serves as a reminder that our God is himself the Great Feast: “Come, everyone who thirsts, come to the waters; and he who has no money, come, buy and eat! Come, buy wine and milk without money and without price” (Isaiah 55:1).

God himself, in Christ, is the one who satisfies more than the best of foods, and quenches our thirst more than the purest of water, the richest of milk, and the best of wine. In him, our souls “eat what is good” and we “delight [our]selves in rich food” (Isaiah 55:2). He is the one who says, “To the thirsty I will give from the spring of the water of life without payment” (Revelation 21:6). We who have tasted and seen his goodness (Psalm 34:8) now join his Spirit in saying, “Let the one who is thirsty come; let the one who desires take the water of life without price” (Revelation 22:17).

Turn Your Aches upon Jesus

When we fast, the aches in our stomachs and pains in our gut are reminders that Jesus is the true food, not our daily bread, and that Jesus is the true drink, not our typical beverages. Christians will fast, as Jesus promised, because as people of faith, we know that believing in him means coming to him to satisfy our soul’s hunger and quench our soul’s thirst (John 6:35) — and one of the best regular reminders of it can be abstaining temporarily from other food and drink.

The great (and often hidden) reward of fasting is God himself. “Open your mouth wide,” he says, as we empty our stomachs, “and I will fill it” (Psalm 81:10). God rewards Christian fasting because it attunes us to the very purpose of God in the universe: to magnify himself in our desiring, enjoying, and being satisfied in him. And he rewards it not just with what we’re asking for with our fast, but ultimately with who he is as our desire, enjoyment, and satisfaction.

Christian fasting is not mainly about what we go without, but who we want more of.