I don’t understand why I’d make a vow to God that I’m going to do fast at some time in the future. Plan, maybe, but not vow. That’s like saying, “come hell or high water,” well here comes high temperature – oops should have left an out. Why not say instead, “Lord, if it be your will, I desire to fast on the following days.” Then if you get sick and you don’t believe God wants you to become more sick by fasting, then you’re covered. If it be for some reasons such as, “oh well I changed my mind just for today,” with no real reason, then you still have to reconcile that with your stated desire.
James 4:13-16
Come now, you who say, “Today or tomorrow we shall go into such and such a town, spend a year there doing business, and make a profit”— you have no idea what your life will be like tomorrow. You are a puff of smoke that appears briefly and then disappears. Instead you should say, “If the Lord wills it, we shall live to do this or that.” But now you are boasting in your arrogance. All such boasting is evil.
Matt 5:33-37
“Again you have heard that it was said to your ancestors, ‘Do not take a false oath, but make good to the Lord all that you vow.’ But I say to you, do not swear at all; not by heaven, for it is God’s throne; nor by the earth, for it is his footstool; nor by Jerusalem, for it is the city of the great King. Do not swear by your head, for you cannot make a single hair white or black. Let your ‘Yes’ mean ‘Yes,’ and your ‘No’ mean ‘No.’ Anything more is from the evil one."
Food for thought…
Alan