When we look in the Old Testament of the Bible we see lots of examples of men and women being called by God to do incredible and hard things. We also see lots of examples of them not finishing the job! Like in our own lives, when God calls us to do something, but we don't do it, these men and women in the Old Testament discovered it could undo everything else!
When you leave God's will undone, it will undo everything else.
2 Kings 23:13