Since it is the truth that sets us free, we need to realize that it is error that makes us slaves to sin. It is untruth that binds us. We will not fall victim to the sin of gluttony or any other sin until we believe a lie, or a half-lie, or a series of lies. Usually we tell ourselves these lies until we believe them and act on them. That is why the Scriptures so frequently warn us not to deceive ourselves. These warnings are usually in the context of temptation to sin. Satan can deceive us, others can deceive us, and we can and often do deceive ourselves.
Here is an example. I have a tendency to deceive myself in the area of how much food I have eaten. I tend to estimate low. Once I was eating frozen fruit sorbet. I bought it because it was fat-free. It had only 150 calories per serving and no fat. So I bought it and I ate it and I tried not to think of the fact that it contained six servings. Now that is six, one hundred and fifty-calorie servings for a total of almost 1,000 calories. I deceived myself into believing that I was eating a low calorie food and ate almost half of my total calories for the day in one dessert.
So here is an idea that will help you avoid deceiving yourself. Decide ahead of time how many calories you need to eat to maintain your weight or lose weight. Write down everything you eat including an careful estimation of how many calories you ate. Estimate a little high. Be careful not to deceive yourself. Satan never gets us to sin without getting us to doubt the goodness of God first.
Write out James 1:14-17 and read it over and over again when you are tempted to doubt the goodness of God and give in to temptation.
“But each one is tempted when he is drawn away by his own desires and enticed. 15 Then, when desire has conceived, it gives birth to sin; and sin, when it is full-grown, brings forth death. 16 Do not be deceived, my beloved brethren. 17 Every good gift and every perfect gift is from above, and comes down from the Father of lights, with whom there is no variation or shadow of turning.” (James 1:14-17 NKJV)