A few years ago, I addressed the topic of fasting and we placed an insert in the bulletin with some basic info on the what, why, and how of fasting. Someone wrote me this week and suggested that we make it available again as we follow through on Alex's challenge. So, here it is (slightly updated):
Fasting: What, Why, How
1) What is fasting?
“Voluntary abstinence from food for spiritual purposes” (Whitney, Spiritual Disciplines of Christian Life).
2) Why fast?
There is no spiritual magic to fasting. We can never manipulate or coerce God (Ps. 115:3). Fasting is not a means of meriting favor or earning blessings. We can never put God in our debt (Rom. 11:35). Fasting, instead, is a God-ordained means of GRACE, just like prayer.
God doesn’t need our prayers, but prayer is a normal means of grace. God doesn’t need our fasts, but fasting is a normal means of grace. Jesus clearly said “when you fast,” not “if you fast” (Mt. 6:16).
Sometimes the motivation for fasting is spontaneous. The need is so great that you can’t do otherwise (e.g. a wayward child, devastating loss, etc.). Usually, however, the motivation will flow out of a settled desire to see change (e.g. a spiritual breakthrough), seek guidance on a major decision, or experience God’s blessing (Mt. 6:18) in some important aspect of life.
The purpose of fasting is to deny physical hunger for the sake of heightening hunger for God and His will. You “say” with a fast:
“God, I want you and your blessing more than I want food.”
“I do not want to be mastered by anything but you.”
“I don’t want my stomach to be my god. I want you to rule me, not my appetites. You are my God.”
3) How do you fast?
A few practical bits of advice might help as you take up Alex’s invitation to fast for at least one 24 hour period in the month of January:
Work your way into it. If you’re not a runner, it’s not wise to begin with 5 miles on your first day. Start with one or two meals the first time and work your way from there.
Replace your normal meal time with time in prayer. The physical hunger pains remind you of the purpose of your fast. They can serve as alarm clocks for prayer.
Feed your faith with the promise of Matt 6:18. It helps to remind yourself why you’re doing this fast, and what you’re after.
Grab a sticky note and write "What I'm hungry for today:" on the top. Make a short bullet list of the purposes for your fast to guide your prayers throughout the day.
Drink water. There’s nothing spiritual about dehydration.
Expect it to be a struggle. Don’t be too quick to give in or depend on something other than God. Remember (Alex made this point so well in his message): the irritability, impatience, etc. that rise up are not reasons to quit. Fasting often functions like spiritual detox, exposing the sludge that is in our souls.
Modify if necessary. Assuming the previous point, some people find they do much better if they drink a little juice while they fast. They simply get too weak and can't function well without it. You might be one of them.
Don’t be mechanical. Be sure not to think about fasting in mechanical or formulaic terms. This is a relational process with your Heavenly Father (e.g. – “If I drink a little juice in the morning, does it still count?”).
If you can’t fast for health reasons (e.g. pregnancy, diabetes), don’t feel guilty. The Lord knows your physical limitations. You can still set aside time to seek him with special intensity.
For further study see the chapter on fasting in Whitney’s Spiritual Disciplines of the Christian Life or A Hunger For God by John Piper.