Read: Matthew 6:16-18
"And when you fast, do not look gloomy like the hypocrites, for they disfigure their faces that their fasting may be seen by others. Truly, I say to you, they have received their reward. (Matthew 6:16 ESV)
One of the repeating themes in Jesus' Sermon on the Mount is the notion of prideful religious display. Jesus did not like the way the Pharisees regularly paraded their superficial religiosity around for everyone to see. He cautioned his followers against that kind of conduct.
I do not like to fast. It's one of the spiritual disciplines that I am really just not a big fan of. But I do it. I don't make a habit of it. I reserve it for significant moments of decision or when I feel like God has specifically asked me to do it. I also try really hard to make it a private matter between me, my family, and God.
That is my personal conviction about fasting. I truly, deeply, believe it is a biblically sound approach. I think God blesses our efforts to please Him in a special way when we make it a secret action between Father and child. I wonder, what other spiritual disciples can we practice in our lives more authentically by making them less public?