"... not one stone will be left on another ..." (Luke 21:6)

"As for what you see here, the time will come when not one stone will be left on another; every one of them will be thrown down." (Luke 21:6)
Jesus is responding to something his disciples said:
Some of his disciples were remarking about how the temple was adorned with beautiful stones and with gifts dedicated to God. But Jesus said, (Luke 21:5)

Why would Jesus respond in this way?

Some preach about how Jesus was predicting the end of the world. Why would he predict something that would not happen anytime in the near future for those around him? Such a proposition is illogical and inaccurate.

However, Jesus stated this around the year 32 A.D. Three decades later, in 66 A.D., the temple in Jerusalem was ransacked by the Romans, and burnt to the ground.

So truly, there did come a time - within three decades and during the lifetimes of many of Jesus' followers - when the temple was torn down and what Jesus predicted came to pass.

But Jesus is also pointing out something else in this statement. Yes, he is talking about the temple being ransacked and torn down. But there is another lesson Jesus is trying to teach. What is it?

That the forms and names of this material world are temporary. In due time, everything in the physical world decomposes and falls apart. And the chemicals that made up the forms we see now will become other forms later.

That goes for buildings as well as bodies. A building might last a few decades before it will begin to naturally fall apart. Or an earthquake or tornado might hit it and it falls apart sooner.

Doesn't every body die?

The same goes for the physical body. Within a few decades, every physical body will die.

But even when the body is alive, the atoms making up the physical body - the carbons, hydrogens and so on - are constantly being exchanged for new ones. Within five years, much of the body's chemicals have been exchanged for new ones. This means our bodies are constantly recycling. They are not these solid and permanent structures of matter. They are fluid - like a waterfall.

Consider stopping and looking at a waterfall. The water that you initially see is falling down the waterfall and going downstream. That water that we are looking at now will be gone within a few seconds, only to be replaced by new water. Thus while we might think it is the same waterfall, in fact, every time we look at it, it is a different waterfall.

This is the same with our physical body because the atoms making up our body are constantly being replaced by new atoms. The body we see in the mirror today is not the same body we were wearing five years ago - most of the atoms have been replaced.

So what is permanent? Since the forms of this world - the buildings and the bodies - are all temporary, where is the permanency?

There is no permanency within the material dimension. But there is permanency within self - the soul.

We are speaking of the eternal self - the person who occupies the physical body. This is the "I" who observes the body and the buildings as they are disintegrating. This is the "I" who wonders about our existence. This is the person within. The person who becomes shocked at the body's age. The person who wants to dress up or cover up the body in some way so it will look younger - or older - or just different.

We are speaking of the soul - the person within the body. We are not made of matter - we are made of spirit.

And each of us is made of spirit - and each of us is eternal. Our composition is spirit and our lifetime is eternal.

Why do we forget who we are?

When we identify with the temporary physical body, we naturally become enamored with the forms of this temporary physical world. That's how we fall into illusion. We see ourselves as something we are not, and in illusion, we think the forms around us are permanent, and we ignore the importance of our relationship with God. Jesus communicated this with his analogy of the house built on the sand:
"But everyone who hears these words of mine and does not put them into practice is like a foolish man who built his house on sand. The rain came down, the streams rose, and the winds blew and beat against that house, and it fell with a great crash." (Matt. 7:26-27)
Jesus is trying to teach his students that the forms and bodies of this world are not permanent. Jesus is trying to point his students in the direction of their eternal existence within the spiritual realm - and their eternal Best Friend, the Supreme Being.

God is never affected by the decomposition of the material world. He is the Creator of the material world. And He created each of us for the purpose of being His loving servants and friends.

Why is this world temporary?

So why did He create this material world as temporary? Why didn't He create a permanent material world to match with the permanent spiritual realm?

Because this is not our home. The Supreme Being created the material world for those of us who wanted to get away from Him. He created the material world as a place where we could pretend that He doesn't exist for a while. He created the material world for us to try to be independent of Him.

But we are not independent of Him. We will never be happy away from Him. We might look high and low for fulfillment throughout this temporary material world, but we will never find it.

We might find fame and money. We might build a big house and have a beautiful spouse with lots of obedient kids running around. But we still won't be satisfied. We still won't be happy. We'll still want more.

This is because we will always be empty without our relationship with God. The Supreme Being created us to be with Him. He created us to be His loving servants and friends. He created us to share life with Him. So when we are not with Him - loving Him and serving Him - we become empty, sad, and alone.

This is why we search the world high and low for that one special "soul mate." Because we need to find that perfect person for us. Our perfect soul mate is the Perfect Person - the Supreme Being.

This is why Jesus' most important teaching was:
“ ‘Love the Lord your God with all your heart and with all your soul and with all your strength and with all your mind'" (Luke 10:27)