Marie asked: “Should Christians fast? And if so, is it no food and only water? And for how long and how often?"
Fasting was part of the rituals in the Old Testament law. The Jews were commanded to fast between festivals. The book of Acts records believers fasting before they made some important decisions. You see that in Acts 1-14.
Having said that, there is no command for New Testament believers to fast.
When Christians do fast, I think it’s wise to do so with caution. It’s tempting to think that fasting will get God’s attention more than not fasting. It’s tempting to think that if I’m willing to suffer the hardship of fasting, God will be more inclined to hear my prayers. Be very careful about that kind of thinking. God’s love for you is not based on how much self-denial you exhibit. It’s based on the gospel work of Jesus Christ.
Taking a fast over lunch because that’s the only time you could pray that day would be very appropriate. Taking a fast because you think God will love you more if your stomach is growling is not a good reason to fast.
Thanks for your question,