We are currently deep into the season of Lent (the word means springtime, the time when days lengthen). One of the ancient customs among Christians during this season is fasting. Lutherans, following their catechism, have taught that "fasting and bodily preparation are indeed a fine, outward training." However, very few of us--myself included--have ever done much of it.
In searching the Internet I found a balanced and helpful website you may want to look at in that connection: Biblical Fasting: What It Is and How to Do It. Dennis Rupert, the author writes, "...I don't want you to feel overwhelmed by the thought of going without food for days and days. There are types of fasting that don't involve such a radical commitment. The Bible gives examples of many different kinds of fasting. " He goes on to tell about three types of fasts:
1. The Normal Fast - One 24 hr. day, from sunset to sunset, based upon the Old Covenant's Day of Atonement (Leviticus 16:29;23:32). Other than not eating, no details are provided. Drinking water is not forbidden.
2. The Partial Fast practiced by the famous "three men in the fiery furnace," Shadrach, Meshach and Abednego, together with Daniel (Daniel 1:15). They ate only vegetables and water, a healthy diet promoted by many in our day. You may even be a vegetarian yourself and not consider this to be a fast at all. However, for those of us who are not vegetarians, this may indeed be the place to start.
3. The Radical Fast during which you go without food for an extended period of time. The 40 days of Lent are built around our Lord's 40 day fast at the beginning of his public ministry (Matthew 4:1-11). This was also a re-enactment of the 40 years during which the Children of Israel were tested in the wilderness--and failed (1 Corinthians 10).
Following up on that history, the Apostle Paul wrote that everything is permissible, but not everything is beneficial or constructive. That's why Lutherans have not been big on fasting, I suppose. It really isn't the matter of denying yourself food. The issue is that of training yourself to trust the Lord and His Word completely and radically. Interesting is the fact that the Word of God nowhere commands New Testament Christians to fast. Two Bible passages come to mind.
1 Timothy 4:8 - "For physical training is of some value, but godliness has value for all things, holding promise for both the present life and the life to come." The Apostle's point is that godliness and reverence do not come from something you do, including fasting. They are what God does in and through His Word. The Word is the means used by the Holy Spirit to renew the image of God within.
1 Corinthians 9:24-27 - In this passage the Apostle speaks about how he disciplines his body as athletes do in preparation for the various contests. He follows this comment with a discussion about Israel's wilderness journey in which they fell deep into temptation and lost any rights to the promised land. He ends that discussion with a Gospel promise. You can depend upon God, he says, because he will never allow a temptation greater than you can bear. He will always show a way out.
If you fast during this Lenten season or at any other time, be aware that the whole discipline can be useful, but it is not a means of grace, a means through which the Holy Spirit works to strengthen and nourish faith and trust. That He always does through His Word and through the visible Words of the Lord's Supper and Holy Baptism.