Jesus nut

From Wikipedia: "Jesus nut or Jesus pin are colloquialisms for the main rotor retaining nut that holds the main rotor to the mast of some helicopters, such as the UH-1 Iroquois helicopter.

The term may have come from the idea that, if the Jesus pin were to fail in flight, the helicopter would detach from the rotors. and the only thing left for the crew to do would be to pray to Jesus. In addition, a person must have faith in the Jesus bolt to do its intended job without failure. Real examples of the Jesus pin failing are few and far between. However the pin must be checked before the flight. Some more recent helicopter systems do not have a Jesus nut."

Not from Wikipedia:  Though this sounds like a topic to make some type of hackneyed postcard out of, I think this is a great way to explain the Christian faith.  Maybe you are offended that the name of Jesus is being used in this way.  I know I was initially.  But I think there is a powerful analogy here.  

Many people think Christianity is an equation that says, "Jesus + my effort = salvation".  The false idea that we are earning our salvation is so entrenched in people's hearts.  So many Christians I know consider their faith in Jesus as "the first step" and then they think they are justified by law and their own performance after that.  That is why I love this idea of the "Jesus nut".  

In aerospace, nearly every design that is critical in keeping the aircraft in the air has some type of redundancy or backup built in.  There is of course, more safety in that approach, and the failure of any one part should not mean disaster for the passengers.  Through legalism, Christians are seeking to be justified by Christ AND by their own works.  But the scriptures make it clear that we must pick one or the other.  There is no backup plan.  

"You who are trying to be justified by law have been alienated from Christ; you have fallen away from grace." -Galatians 5:4

You are riding in the helicopter.  There is a single nut that holds the rotor in place.  Your life is inextricably tied to the success or failure of that one thing.  Do you put your faith in Christ, or in your own ability to keep the law?