There was a certain man who was born on earth into a natural realm.
Every message of that realm promised him life but only gave him death!

Proverbs 14:12
There is a way that seems right to a man,
but in the end it leads to death.

He went through the ups and downs of life feeling 'high' and 'low' respectively then thereafter 'empty' not knowing the real purpose of his life!

Eccl.1:2
"Meaningless! Meaningless!"
says the Teacher.
"Utterly meaningless!
Everything is meaningless."

One day, he heard a new voice with a new message about a new realm.
This realm was actually greater than his natural visible realm though it was invisible!

John 3:31
"The one who comes from above is above all; the one who is from the earth belongs to the earth, and speaks as one from the earth. The one who comes from heaven is above all.

The message was that he had to be born by a new invisible force into the new realm.

John 3:3, 5, 6, 8
In reply Jesus declared, "I tell you the truth, no one can see the kingdom of God unless he is born again."
Jesus answered, "I tell you the truth, no one can enter the kingdom of God unless he is born of water and the Spirit.
Flesh gives birth to flesh, but the Spirit gives birth to spirit.
The wind blows wherever it pleases. You hear its sound, but you cannot tell where it comes from or where it is going. So it is with everyone born of the Spirit."

When he received this new message, he became born anew into the new realm.

John 1:12, 13
Yet to all who received him, to those who believed in his name, he gave the right to become children of God
children born not of natural descent, nor of human decision or a husband's will, but born of God.

In this new realm was all that he needed to be, to have, and to do so as to fulfil the purpose for which he was born on earth!
But he started having a clash of influence within his soul which threatened the fulfillment of that purpose.

Gal.5:17
For the sinful nature desires what is contrary to the Spirit and the Spirit what is contrary to the sinful nature. They are in conflict with each other, so that you do not do what you want.

This clash was because the forces of both realms were opposed to each other.
When he tried in his own natural way to fulfil this purpose he got frustrated by the natural realm.

Rom.7:18-20
I know that nothing good lives in me, that is, in my sinful nature. For I have the desire to do what is good, but I cannot carry it out.
For what I do is not the good I want to do; no, the evil I do not want to do-this I keep on doing.
Now if I do what I do not want to do, it is no longer I who do it, but it is sin living in me that does it.

But when he focused and relied on the invisible force of the invisible realm within him he was liberated and thereafter he made progress in fulfilling his purpose.

Rom.8:2, 5, 6
because through Christ Jesus the law of the Spirit of life set me free from the law of sin and death.
Those who live according to the sinful nature have their minds set on what that nature desires; but those who live in accordance with the Spirit have their minds set on what the Spirit desires.
The mind of sinful man is death, but the mind controlled by the Spirit is life and peace;

The evidence of such progress is:-

Gal.5:22-23
But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness,
gentleness and self-control. Against such things there is no law.

But whenever he focused and relied on the natural force he lost progress in that direction.
Instead he produced works of the natural force:-

Gal.5:19-21
The acts of the sinful nature are obvious: sexual immorality, impurity and debauchery;
idolatry and witchcraft; hatred, discord, jealousy, fits of rage, selfish ambition, dissensions, factions
and envy; drunkenness, orgies, and the like. I warn you, as I did before, that those who live like this will not inherit the kingdom of God.

Therefore to maintain such progress he had to keep focusing and relying on the invisible force within him!!!

Gal.5:16, 25
So I say, live by the Spirit, and you will not gratify the desires of the sinful nature.
Since we live by the Spirit, let us keep in step with the Spirit.

The natural realm is the world system on earth; and the new realm is the kingdom of God.
The new message is the gospel of God.
The point of entry into the kingdom of God is the Lord Jesus Christ,the Son of God:

John 10:9
I am the gate; whoever enters through me will be saved. He will come in and go out, and find pasture.

The natural force is the physical and mental faculties of the person independent of the Spirit of God; while the invisible force is the Spirit of God which eventually resides within him.
The purpose of the person is his divine destiny on earth!

Bible quotations above are from the New International Version (INV)