How does the level of sacrifice effect a fast? I can tell you that I could give up spinach for a year easier than fasting from coffee for a single day. Although I have practiced limited fasting somewhat regularly, I am certainly not an expert on the subject. I have not studied it nor have I read any books devoted solely to it's topic. Perhaps I should.
Imagine your fasting from all food, it's the second week and you have two more to go. I'm not asking you to think about how famished you're feeling, because the hunger is likely much easier by now than at the beginning, but rather what are you expecting from your fast.
I'll admit that most of the times I fast is because I really want God to do something for me. Answer my prayer...now,...please! Fasting is a way of showing our commitment to a cause or desire. King David said that he would “not sacrifice a burnt offering that costs me nothing.” 1 Chronicles 21:24
Can we fast to change ourselves? If I fasted for 40 days, you bet I would want to be changed because of it. Education, study, exercise and diet are all purposed for the betterment of ourselves. Why are we willing to devote four or more years of our life, tens of thousands of dollars for an education, if we didn't value the outcome? A specific career or higher financial opportunities are our rewards.
If an extended fast, an overnight stay in a homeless shelter or a trip to a third world country could change our lives then why aren't we doing it? Are we willing to invest in Gods kingdom here on earth? Are we pursuing a life that is at the foot of the cross. Do our hearts break over the lost people we know? Do we long for just 30 more minutes of prayer before we have to go to work. Are we wanting a life that looks more like Jesus or are we doing OK for ourselves now? I personally want more, I want His kingdom to come here on earth and I want to be a part of it. This is not about legalism or works, it's about putting on the mind of Christ and walking in step with the Spirit. It's about falling in love with Jesus.
Jesus asked Peter three times if he loved Him. Each time Peter responded yes Lord you know that I love You, and each time, Jesus followed with “then feed my sheep”. When I get real honest, I think God wants a lot more from me than what He's been getting. He wants all of me and all of you.