"'Now, therefore,' says the Lord, 'Turn to Me with all your heart, with fasting . . ." (Joel 2:12).

The only thing most people know about fasting is that it can be a way to lose weight. But there's much more we need to understand about fasting than that.

The Bible has much to say about this very important but often-neglected spiritual key. God desires and expects His followers to fast. Jesus Christ was asked why His disciples did not fast like other religious people. He replied with a short parable explaining that it was because He was still present with His disciples. He stated that after He was no longer among them (referring to His impending return to heaven), "then they will fast" (Matthew 9:14-15).

By that He meant that all of His future disciples would fast. Why? Because we need fasting with prayer to help us maintain a close relationship with God the Father and Jesus Christ. And there are other major spiritual benefits of fasting, as we shall see.

When Jesus spoke to His disciples about how to fast, He clearly was expecting that they would fast (Matthew 6:16-18). He did not say "if you fast" but "when you fast." And note that in this chapter, Jesus emphasizes fasting as much as praying and doing good works.

Fasting is mentioned prominently in the Old and New Testaments. The biblical record of who fasted is a virtual "who's who" of the Bible and includes Moses, David, Elijah, Ezra, Nehemiah, Esther, Daniel, Anna and Jesus Christ. The apostle Paul engaged "in fastings often" (2 Corinthians 11:27).

What is fasting?

In a sense, everyone fasts. When we are in bed asleep, we go without any food or drink. That is fasting. That is why the first meal of the day is called breakfast. However, when people speak of fasting, they usually mean a longer period of time of deliberately choosing not to eat and drink. It can be for a whole day, part of a day or more than a day.

A health fast is any temporary restricted diet that is supposed to have certain health benefits. But we are addressing fasting for one's spiritual health, which involves abstaining from food and drink while spending a lot of extra time in prayer, meditation and Bible study (Exodus 34:28; Ezra 10:6; Esther 4:16; Acts 9:9).

Ideally, we should spend most of the waking part of a fast period praying, studying and reflecting. If this is not possible, at the very least we can do that during the extra time when we ordinarily would be eating.

Misunderstandings about fasting

A healthy person who is not perspiring much can go without food and water for about three days before the body begins to be stressed. And a healthy person can go without food for several days if he is drinking water. Thus, the amazingly long 40-day fasts by Moses, Elijah and Jesus Christ (Deuteronomy 9:9; 1 Kings 19:8; Luke 4:2) were possible only by God's supernatural intervention.

How long we might safely fast depends on our individual health. If you are unsure about your health limitations, it would be wise to get a medical checkup, and we strongly advise it. Then start with skipping a meal or two before gradually increasing to a full day fast—being alert to the beginning of any adverse effects.

However, we shouldn't consider mere discomforts—including feeling hungry, thirsty and less energetic—as "adverse effects." For most people, a headache is simply a symptom of withdrawal from regular caffeine consumption. It's wise to taper off from caffeinated beverages before beginning a fast.

Another option is a partial fast, such as that mentioned in Daniel 10:3. Here one takes in only as much food and/or water as necessary to be safe and spends extra time in prayer, Bible study and meditation. This, too, can be very profitable spiritually.

Fasting is unpopular in a culture of instant self-gratification. People tend to think that every day they need three large meals plus snacks. In a culture of continual feasting, it seems there is no place for fasting! From that standpoint alone, fasting is good for character building—developing self-discipline, commitment, moderation and better eating habits.

Important reasons for fasting

Fasting is an important part of building a right and strong relationship with God (Luke 2:36-37; Acts 13:2).

Godly fasting is poles apart from hunger strikes used to gain political power or draw attention to a personal cause. Fasting is an exercise in self-discipline over our fleshly cravings while keeping God first in our thoughts. It liberates us from slavery to our appetites while we focus on the true "Bread of Life," Jesus Christ (John 6:48-51, John 6:63). When fasting, we make a small self-sacrifice to focus on our Savior's awesome sacrifice and plan for us.

By nature we are egocentric (self-centered), and must work at becoming God-centered. A major purpose of fasting is to learn humility—to better understand how great God is and how weak, sinful and needy we are. King David understood this when he wrote, "I humbled myself with fasting" (Psalm 35:13).

God delights in humble hearts. He said in Isaiah 66:2, "This is the one I esteem: he who is humble and contrite in spirit, and trembles at my word" (NIV). In Matthew 5:3 Jesus said, "Blessed are the poor in spirit [humble and dependent], for theirs is the kingdom of heaven."

Jesus made it clear that if we fast to show off—to "appear to men to be fasting"—we are hypocrites and will have no reward from God (Matthew 6:16-18). Jesus did not mean that it's always wrong to tell someone you're fasting. Often there's a practical need to tell someone, like your spouse. Jesus was talking about the necessity of right motives and attitudes.

Jesus spoke a parable in which a proud Pharisee bragged to God, "I fast twice a week" (Luke 18:9: Luke 18:12). The man imagined himself to be humble and was proud of it! Fasting with such a conceited attitude is worthless.

God wants us to "hunger and thirst for righteousness" (Matthew 5:6). When we fast, we increasingly feel hungry and physically weak. In addition to reinforcing the fact that God is the One who sustains us and supplies all our needs, an important lesson of this is that we rapidly become weaker spiritually when we neglect the nourishment of prayer, Bible study and all other efforts to be God's spiritually transformed sons and daughters.

The Bible has only one command regarding when to fast. God's people are commanded in Leviticus 23 to fast on the Day of Atonement for 24 hours—from sundown to sundown (Leviticus 23:27-32). This fast day is listed here among God's annual appointed times or spiritual feast days.

Besides the ordinary personal benefits of fasting, the Atonement fast has prophetic significance. To learn about the meaning of the Day of Atonement and its accompanying fasting, read the free Bible study aid God's Holy Day Plan: The Promise of Hope for All Mankind.

Secondary purposes of fasting

Besides the primary purposes of worshipping God, drawing closer to Him, denying and humbling ourselves and growing spiritually, it is appropriate to have secondary purposes in fasting as well—beseeching God in prayer for His help with one or more serious needs for ourselves or for others.

When God has not answered prayers for a certain need, try fasting with prayer. In one instance when His disciples could not cast out a demon, Jesus told them that "this kind does not go out except by prayer and fasting" (Matthew 17:14-21). Proper fasting often results in significant spiritual breakthroughs. While we rely on the spiritual tools of prayer, Bible study and meditation on a daily basis, we occasionally need the power tool of fasting.

There can be many reasons to fast, such as a personal problem, a difficult-to-overcome sin, facing a major decision, a Church crisis, a threat of danger, the need to change someone's attitude, or expressing thanksgiving, among others. For a very enlightening study, use a Bible concordance and look up all the passages that contain the words fast, fasted and fasting. Read why people fasted, what they were praying about and what God did as a result of the fast.

However, we must never view fasting as pressuring God to get what we want (Isaiah 58:3). God wants us to pray about our problems, but not to try to dictate the solutions. Our attitudes should be like that of Jesus Christ when He prayed, "Not My will, but Yours, be done" (Luke 22:42).

It is fine for a group such as a church congregation or circle of friends to decide to fast together concerning an urgent matter. When his country was being invaded, King Jehoshaphat "proclaimed a fast throughout all Judah" (2 Chronicles 20:1-3). At the preaching of Jonah, "the people of Nineveh believed God [and] proclaimed a fast" (Jonah 3:5).

To beseech God for His protection, Ezra proclaimed a fast for all the exiles returning to Judah (Ezra 8:21-23). Esther requested that all the Jews in the Persian capital city fast so that they would be spared from genocide (Esther 4:16).

Isaiah 58:1-12 is a profound passage that contrasts right and wrong attitudes in fasting. It clearly shows that fasting must not be a mere ritual. Fasting should teach us to be willing to sacrifice in many ways in the service of others. How much are we willing to sacrifice to "undo . . . heavy burdens, to let the oppressed go free . . . to share your bread with the hungry, and that you bring to your house the poor who are cast out; when you see the naked, that you cover him?" (Isaiah 58:6-7).

God's Word exhorts us to "stand fast in the Lord" (Philippians 4:1; 1 Thessalonians 3:8). Here the English word "fast" means firmly fixed or steadfast. From what the Bible teaches us about fasting, we see that people who sincerely and regularly fast and pray to God will very likely "stand fast in the Lord"!