I recently had a complex mold built.  The part shape is such that if the mold opens in the wrong  sequence, it will ruin the steel blocks that shape the part within the mold.  It would be very costly.  There is a plate that must move in order to drive the slides out to release the part undercut shape before the core is withdrawn.  If this doesn’t happen, the cores will run into the slides and wreck everything.  In order to prevent a crash, I added redundancy.  There are mechanisms that move the plate and then release it.  These are called latch locks.  Sometimes we use two of them, but this mold has four of them.  We also added springs to help move the plate, and beyond that, we added air cylinders to assist with moving the plate.

Sometimes you can use a redundant system in order to ensure that something catastrophic cannot happen.  But sometimes a redundant system would not allow the system to function properly, so the one critical part that performs a vital function just has to be made as robust as possible. 

In this mold, there can be no redundant cavities and slides.  They are the critical parts that must work correctly.

For example, an airplane can have redundant hydraulic systems, but an airplane cannot have  a redundant wing.  There can be only one left wing, and it must work and not fail.  It’s not like you can just fasten a couple more spare wings onto the main wing.  The spare wings would inhibit the function of the main wing.

Whether you realize it or not, God employs these ideas in our salvation.  There is only one Savior.  It is critical that we believe in Him alone for our salvation.  We can’t carry other spare ‘saviors’ just in case Christ is not enough.  If you have other spare ‘saviors’ that you are hoping will save you in case Christ were to fail, then salvation will be inhibited and you will be lost.  Some people might want to use their own good works as a back up plan.  Maybe, they think, if only I am good enough God would accept me.  Do you think that Jesus is not able to do enough to save you, but you could?  No. There can be no spare savior.  Only God through the work of Jesus is able to save.  Jesus is critical to salvation.  There is no back up plan.  Christ must work, and He will work.  His work of salvation is enough, it is complete, and there can be no other. 

Having said that, once one has trusted in Christ alone, God does employ redundancy.  John 10:27-29  says, “My sheep hear my voice, and I know them, and they follow me:  And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.  My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father’s hand.”  Once we have trusted in Christ for our salvation we are held securely in Christ’s hand, and in case that were to fail (but it never will), God the Father also has a redundant protection in place.  Nobody is going to get us out of the Father’s hand.  Nobody is going to be able to get at us to take us away.  No one is going to be able to overcome both God the Father and God the Son to get at us.  Why does God guard those He saves so closely?  It is because we are His children.  Jesus loves us enough to give His life for us.  God the Father loves us enough to give His Son for us.  We are most precious to God.  He will never give us up.  He puts us in the most secure place in the universe.