Jesus knows the reasons men do religious things. Usually, it is to be seen, it’s that darn flesh crying out to be seen. That body of flesh that craves attention. And if it drives the soul, well, that is very, very sad. It would keep us away from the dynamic relationship God has for us in the Spirit.
“Now whenever you fast, do not make a gloomy face as the hypocrites do, for they distort their faces so that they will be noticed by people when they are fasting. Truly I say to you, they have their reward in full. But as for you, when you fast, anoint your head and wash your face, so that your fasting will not be noticed by people but by your Father who is in secret; and your Father who sees what is done in secret will reward you.” (Matthew 6:16-18 NASB)
Can you imagine moping around, and purposely looking like you were on the verge of death, just to get people to believe that you were something that you were not? The religious pretend. I have seen stranger behaviors of the flesh, than fasting for attention. People will go to extremes when acting spiritual, especially in the company of their peers. Does this explain the wild church things that Jesus would never do, called demonstrations of the Holy Spirit? Religion offers a very popular way to get attention. But not if it is God’s glory and His attention we seek.
To fast or not to fast, that is a question for Jesus. How to fast He has answered.