An Introduction to Fasting

Fasting is a powerful but often neglected spiritual discipline of the modern Western church.

Jesus said there are spiritual demons that cannot be cast out without the power of fasting.  “He replied, ‘This kind can come out only by prayer and fasting.’” (Mark 9:29)  Jesus also fasted for 40 days before he faced the temptation of Satan and before he began his public ministry.

Fasting provides power to our prayers that prayer alone does not accomplish.  Fasting breaks things loose that cannot come loose by prayer alone.

People practiced the discipline of fasting in both the Old and New Testaments.  Moses fasted at least two recorded forty-day periods. Jesus fasted 40 days and the early church fasted before sending Paul and Barnabas on their first missionary journey.

Jesus began his teaching on fasting in Matthew 6 with “when you fast.”  Jesus did not command fasting, but describes the spiritual activity the church will undertake after He ascended to heaven.  The church will engage in the spiritual discipline of fasting.

Benefits of Fasting

Fasting and prayer can restore the loss of the "first love" for your Lord and result in a more intimate relationship with Christ.

Fasting brings humility before God. (Psalm 35:13; Ezra 8:21). King David said, "I humble myself through fasting." 

Fasting enables the Holy Spirit to reveal your true spiritual condition, resulting in brokenness, repentance, and a transformed life.

Fasting can transform your prayer life into a richer and more personal experience.  You can expect prayers to be answered in dynamic and powerful ways.  You will see things happen that you are not even praying for!

Fasting can result in a dynamic personal revival in your own life-and make you a channel of revival to others.

Fasting has been a major emphasis in the lives of many of the great spiritual leaders throughout history. John Wesley, the founder of the Methodist denomination, fasted every Wednesday and Friday and required all of his clergy to do the same. Effective ministers of God from the apostle Paul to Martin Luther to John Calvin made it a continual part of their walks with God.

None of those men had a "formula fast" that was the only "right" way. Fasting is about the condition of the heart, not the length or type of fast undertaken.

Spiritual Preparation

Fasting is a choice to feast not on Him who is the bread of life.  We seek to have so much of Him that we give up the satisfaction that comes from the temporary things we can partake of.

Fasting is a way of saying that I am not satisfied with these temporary things here.  It is a hunger for God awakened by a taste for God. 

You should include confession of sin as part of the discipline of fasting.

Types of Fasts in the Bible

Various types of fasts are found in the Bible.  Daniel abstained from delicacies, meat, and wine for three weeks.  Absolute fasts involve abstaining from both food and liquids including water. 

Paul engaged in an absolute fast for three days following his encounter with Christ on the road to Damascus.   Moses engaged in an absolute fast of 40 days (Deuteronomy 9) so he must have been supernaturally sustained during his fast.

Most fasts involve fasting from food, but drinking liquids.

Water-only fasts that last for more than several days need to be undertaken with complete rest and under medical supervision because of the extreme danger of over-toxification, breakdown of vital body tissues, and loss of electrolytes.

Water and juice fasting is effective, especially if you are going to fast for an extended period of time.

Physical Preparation

Prepare to fast for several days by gradually reducing the size of your meals.  Do not have “one last big feast” before fasting as it only increases your hunger when you begin fasting. Cutting down on your meals a few days before you begin the fast will signal your mind, stomach, and appetite that less food is acceptable.

Some health professionals suggest eating only raw foods for two days before starting a fast, although I have not found this to be necessary.

You also should gradually exit a fast because your body needs to re-adjust to eating solid foods.  Foods such as apple sauce, yoghurt and soup are great when exiting a fast.  Add in raw fruits and vegetables.  Difficult to digest foods (spicy foods, citrus fruits, meats, foods from dairy such as cheese and high fat foods and highly processed foods) should be the last that you eat after exiting a fast, particularly if it is an extended fast.

Before embarking on an extended fast, begin fasting for one meal a day, or one day a week, or one week a month. Build up the discipline so that you will be prepared for an extended fast of several weeks.

You may notice that you feel cold during extended fasts.  Your metabolism slows and your body is drawing on stores of fat, but with the slowed metabolism you will feel cold especially after drinking cold beverages.  You may need to wear more layers of clothing and drink warm beverages to help counteract this.

You will sleep more and see your physical energy decrease.  Again, this is more pronounced with an extended fast.  You will not want to undertake an extended fast when you will need to be doing significant physical activity. 

Mental Preparation

Prepare yourself mentally to be hungry and to resist the temptation of food.  Visual images of food and smells of foods will be heightened while you fast.  

You also must be prepared to change the habit of eating.  You will begin to realize how often you grab food or eat food without really thinking about it.  You also will discover that you are regularly offered free food (including your favorites) while you are fasting.

Finally, you will see your mood change because of hunger and lower blood sugar.  It is normal, but recognize it and be prepared for it.  It is part of the humility that comes with fasting.

Health Concerns

You may hear from people that fasting is unhealthy. However, fasting, if undertaken properly, brings physical and spiritual blessings.

Consult your doctor before you begin your fast especially if you are on medications. Receiving a physical examine from a doctor to ensure you are healthy enough for fasting is wise.  You may have physical problems that make fasting unwise or dangerous.

Many doctors are not familiar with fasting so realize their understanding of its impact on the body may be limited.

The following people should not fast without medical supervision:

  • Persons who are physically too thin or emaciated.
  • Persons who are prone to anorexia, bulimia, or other behavioral disorders.
  • Those who suffer weakness or anemia.
  • Persons who have tumors, bleeding ulcers, cancer, blood diseases, or who have heart disease.
  • Those who suffer chronic problems with kidneys, liver, lungs, heart, or other important organs.
  • Individuals who take insulin for diabetes, or suffer any other blood sugar problem such as hyperglycemia.
  • Women who are pregnant or nursing.