'Fasting' in the Bible

After fasting for 40 days and 40 nights, he finally became hungry.

"Whenever you fast, don't be gloomy like the hypocrites, because they put on sad faces to show others they are fasting. I tell all of you with certainty, they have their full reward!

so that your fasting will not be noticed by others but by your Father who is in the hidden place. And your Father who watches from the hidden place will reward you."

But this kind does not come out except by prayer and fasting."