The hypothesis that every action or thought has an effect in the future is difficult to prove. If the effect of our actions or thoughts occurs immediately, the relationship would be easy to understand. But the delay may be prolonged, possibly extending to our next lives(reincarnation) or to the after life (heaven or hell). This is why it is difficult to see the relationship between the usage of our mind now, and what happens to us in the future.
God sees the difficulty of us understanding this law of causality, and sees the suffering in the world. God has given us a path to see this relationship. In the Tip of the Writing Brush is the following:
What do you think this path is about?
It is to cleanse the heart of everyone in the world. 16-57
Hereafter, I shall not indicate anyone in particular.
I am watching the innermost heart of each of you. 16-59
I do not indicate anyone in particular by this talk.
I shall give notice through bodily disorders. 16-40
God will begin to lay a special path where cause and effect is seen immediately. The minds of the world will be reflected to God. God will begin to place disorders and illness on our bodies dependent on how we are using our minds today. When we see this immediate relationship between bad thoughts and suffering, and good thoughts and healthy body, we can begin to eliminate evil (greed, arrogance, and self love) from our hearts. Eventually, like the law of gravity, people will accept the law of cause and effect. When this happens, illness and disorders (God’s immediate guidance) will not be needed for us to see this important relationship.
In summary, God has given us this special guidance in making us aware of the law of cause and effect. When everyone understand this important relationship of cause and effect, the world will become joyous, with everyone helping each other.