In a modern culture obsessed with wellness, it is not uncommon for fasting to be part of the discussion. We see it everywhere: intermittent fasting for weight loss, metabolic resets for longevity, and "dopamine fasts" for mental clarity. But for the follower of Jesus, fasting is not a bio-hack, a physical detox, or a path to self-optimization. It is a spiritual necessity that reorients the soul toward its Creator.
To understand biblical fasting, we must first distinguish it from the world's version of fasting. While a diet focuses on the self (my health, my appearance, my discipline), a fast focuses on our Savior. It is the intentional, temporary denial of something good—most commonly food—in order to intensify our hunger for something better. As the old saying goes, we are "abstaining from the earthly to feast on the heavenly."
The "When," Not "If"
In the Sermon on the Mount, Jesus provides instructions on various spiritual disciplines. Crucially, in Matthew 6:16, he doesn't say, "If you fast," as if the practice were a specialized elective for the "super-spiritual." Instead, he says, "When you fast." He places it on the same level as prayer and generosity. To Jesus, fasting was an assumed rhythm of the disciple’s life. It was a practice woven into the very fabric of being a child of God. If we find that fasting is entirely absent from our lives, we aren't just missing out on a bonus blessing; we are neglecting a primary tool Jesus gave us for our own sanctification.
The Muscle of Self-Denial
We live in an age of unprecedented indulgence. We are conditioned to believe that if we have a desire, it must be satisfied immediately. If we are bored, we reach for our phone; if we are lonely, we scroll through social media; if we have a craving, we have a meal delivered to our doorstep within minutes. This constant ‘Yes!’ to our physical appetites weakens our spiritual muscles.
Fasting is a way of exercising the muscle of self-denial. It is a form of spiritual training that counters being mastered by our own flesh. There is a profound theological point to be made here: if you cannot say "no" to a steak or a cup of coffee, how can you expect to have the spiritual fortitude to say "no" to a powerful temptation that threatens your integrity or your marriage? By denying the body its basic needs for a time, we prove to ourselves and remember that we are not under the mastery of our stomachs, but under the control of the Spirit of God.
Then the disciples of John came to him, saying, “Why do we and the Pharisees fast, but your disciples do not fast?” And Jesus said to them, “Can the wedding guests mourn as long as the bridegroom is with them? The days will come when the bridegroom is taken away from them, and then they will fast. No one puts a piece of unshrunk cloth on an old garment, for the patch tears away from the garment, and a worse tear is made. Neither is new wine put into old wineskins. If it is, the skins burst and the wine is spilled and the skins are destroyed. But new wine is put into fresh wineskins, and so both are preserved.” (Matthew 9:14–17)
A Longing for the Wedding Feast
Ultimately, fasting is an act of holy homesickness. In Matthew 9:14-17, Jesus explains that His disciples didn’t fast while He was with them because it’s unthinkable to fast at a wedding when the groom is present and you are in the middle of celebrating something worth celebrating!. But, He says, the days are coming when the groom will be taken away, and then they will fast.
We live in those in-between days Jesus was referring to. We fast because we are not yet home. We fast because the Bridegroom is not physically present, and we long for His return. Every hunger pang is a physical echo of a spiritual reality: this world, as good as it may be, is not our final destination. We are saying, "Lord, I can do without this meal today, because I am looking forward to the Great Marriage Feast of the Lamb that is coming." Fasting keeps us from becoming too comfortable in a world that is passing away.
If you do not have a current fasting rhythm in your life, consider fasting and meditating on 1 John 2:15-17 at some point this week to focus on longing for eternity with God and cultivate your desire for more of him here and now.
Do not love the world or the things in the world. If anyone loves the world, the love of the Father is not in him. For all that is in the world—the desires of the flesh and the desires of the eyes and pride of life—is not from the Father but is from the world. And the world is passing away along with its desires, but whoever does the will of God abides forever. (1 John 2:15-17)