In this portion of the Sermon on the Mount, Jesus continues addressing certain spiritual disciplines. He is taking what the people of the day practiced and is showing how His followers should practice these same things, but with different motives. He has already addressed giving (6:2-4) and prayer (6:5-15). Next He speaks to a topic that is not as commonly addressed in our day: fasting.
Before we address how to fast, we must briefly give a definition for fasting. Fasting was a common practice in Jesus' day. The Jewish people took fasting seriously. In fact, it was commanded to fast on the Day of Atonement (Leviticus 23:26-32). There are many other occasions of fasting recorded in the Old Testament. Fasting meant giving up physical things (specifically, food, most of the time) for the sake of longing for and seeking God. I love the way John Piper defines fasting in his book A Hunger for God:
"Fasting is a way of revealing to ourselves and confessing to our God what is in our hearts. Where do we find our deepest satisfaction--in God or in His gifts? And the aim of fasting is that we come to rely less on food and more on God."
Jesus assumes that His followers would fast, as He states at the beginning of verse 16, "And when you fast...(emphasis added)." There is not an "if," but a "when." Jesus expects that His followers would display their hunger for God by abstaining from food (as well as other physical needs) in order to seek His face.
But not only should we fast, Jesus addresses how we should fast. Like He did with giving and prayer, Jesus addresses the way that the hypocritical spiritual leaders of the day fasted. They only wanted to be seen by others. They wanted the accolades and to be seen as "spiritual giants." They would intentionally not wash their faces and clean themselves up so that it would be evident to those around them that they were trying to be "spiritual" by fasting. They loved the praise of man rather than the worship of God.
It should not be so with Christians. Jesus makes it clear that His followers are to fast as a matter of the heart. It should be between themselves and the Lord. Jesus says: "But when you fast, anoint your head and wash your face, that your fasting may not be seen by others but by your Father who is in secret. And your Father who sees in secret will reward you."
I will leave you with two questions:
1. Christian, do you fast? If not, look at Jesus' words in this passage. He makes it clear that this should be a spiritual discipline that His followers practice. Start small. Maybe fast for lunch one day and use the time you would normally eat to seek the Lord in Word and prayer. Or fast from social media for a day. Or fast from TV for a week. Or a number of other things in order to seek the Lord.
2. When you fast, do you look to God for your reward? Don't do it because you want to impress anyone. And don't do it just because I said so! Do it because you want to reveal to yourself and confess to God that you desire Him above all else. There is a deep delight that comes when we die to ourselves, push away lesser things, and seek the greatest Being in all the universe.
Look to Jesus in fasting. He is greater than any amount of food or social media or TV or anything else that may capture our hearts.