For many, the practice of fasting seems foreign and archaic. Unlike other spiritual disciplines such as prayer or giving, we’re not always given much guidance on how or why we do it.

A friend once enthusiastically launched into her first fast. By the afternoon, clutching her fruit juice, she felt dizzy and defeated. This reminded me how important it is to understand why we fast, as well as how to do it practically.

The biblical purpose of fasting appears primarily to be a means of personal spiritual revival. As the prophet Joel declares, it’s a way of re-aligning our hearts with the Lord, 'Return to me with all your heart, with fasting …' (Joel 2:12-13.). As Bill Bright says, fasting can ‘restore the loss of one’s first love for the Lord’ (Unity In Christ). The act of surrendering something pleasurable is a demonstration of humility (Ezra 8:21). It’s effectively saying ‘My strength ultimately comes from the Lord.’ Fasting is not a command in the bible, but Jesus does say ‘when you fast,’ suggesting that it should be a natural part of our lives (Matthew 6:16).

Practically, it gives us more time to spend in prayer over a certain issue. If fasting during the day, pangs of hunger can serve as a reminder to pray or focus on God. Some people fast one meal a week, using that time to pray.

In its broader definition it seems that fasting could be taking something up – as long as there is genuine sacrifice involved. In Isaiah the Lord declares that the kind of fasting he wants involves loosening the ‘chains of injustice,’ and sharing ‘food with the hungry’ (Isaiah 58:6-7). In this sense, perhaps volunteering in a soup kitchen is a form of fasting?

Interestingly, Richard Foster explains that fasting ‘reveals the things that control us’ meaning it can bring more freedom. We all tend to cover up what is inside us by turning to food or other good things, but in fasting these come to the surface. If jealousy controls us, it will be revealed. When we then take these to the cross, we find Jesus’ forgiveness and are free from their controlling influence.

Additional freedom can be found when we realise how much we are addicted to what we are sacrificing. We might find we are more addicted to Facebook, caffeine or chocolate, than we thought. In his book Fasting, Derek Prince says it can help us establish control over our bodies, ‘Remember, your body is a wonderful servant, but a terrible master.’

In the bible there are three main types of fast: The normal fast, the partial fast and the absolute fast. The normal fast involves abstaining from food but not water (Luke 4:2). The partial fast is a restriction of diet (Daniel 10:3) and the absolute fast involves no food or water (Esther 4:16). This should be done with conviction that the Lord is asking us to do it, and never for more than three days, according to Richard Foster. For further practical advice as to how to fast from food, Foster has some excellent advice in his book Celebration of Discipline.

Consider other types of fasting – How about a technology fast? Alternatively, try the Carbon Fast initiated by Tearfund, in which you take small actions each day to lessen your carbon footprint. Or take something up such as five more minutes in prayer daily (See 24/7 Prayer).

Feel free to add comments below about your personal fasting experiences or those of a friend …