Simple things can make a huge impact when conveying truths about Bible principles. Illustrations don’t have to be fancy by any means, but they need to do what is intended… put light on the subject… not on the illustration.
   A rubber band is a simple but powerful illustration. When dad used it in his lesson on grace, he would simply use it to show how the very essence of God’s grace is that which does not condone sin and imperfection, but accepts in spite of sin and imperfection.. to a point.
   You can stretch a rubber band just so far, and then it breaks. Of course it’s wrong to ‘try’ and ‘stretch’ God’s grace (Romans 6:1-2) yet most have done this. His grace ‘stretches’ though…. that’s the nature of grace (using this illustration). Grace means “unmerited favor”, but what is that, if it isn’t acceptance that cannot be earned or deserved on the basis of how good you are or how perfect you keep commandments. (Keep the commands of Jesus… but don’t depend on your command keeping to save you.) If you ‘merit’ God’s favor, then you have earned it, and God is in debt to you, on the basis of your own life and actions. (Like the worker who comes to the boss and says, PAY ME WHAT I HAVE EARNED!) Who is going to lay claim to ‘meriting’ (earning) God’s favor? Paul said, “There is none righteous, no, not one” (Romans 3:10). Then again in verse  20, “By the works of the law shall no flesh be justified in His sight…” If grace means anything to me, it means room to grow, to get up and ‘try again’ after falling. Like Grandma said to grandpa, who was being a bit tough on little Johnny.. “Give that boy some elbow room!” 
   Can a person lose this great gift of “unmerited favor”? Of course, but too many Christians think that every time one sins, he falls from grace till he publicly confesses and repents and prays, and then the Christian is “back in grace again”. “In and out, in and out…” Are there times for public confession? Yes. However, the idea that grace is so narrow (like walking a tight rope) and rigid that there is no ‘elbow room’ or room for growing, can’t relax and enjoy being saved, no room for mistakes (sin)… in my judgment is not right.
   What about those sins you forget to mention in prayer? What about those sins that you cannot pray about? Suppose you are in a car accident, and end up in a coma before you can repent and pray? Such a picture of grace provides no confidence to the Christian. Yet one can fall from grace, and be lost. When? In short, when a person turns his back totally on Jesus and won’t come back. This means one must repent (turn and come back), but in this case, the person will not ever repent (Hebrews 6:4-6). If he did repent would God receive him? Of course… that’s the nature of God’s love. Yet a heart that is hardened, cannot be molded, changed or taught.
  What can be learned from a rubber band? Well, next time you pick one up, just sit and stretch it and think… God’s grace is so good. He loves and saves even me, and can save you as well.