Sri Chinmoy: Actually, let us not use the word “trial". You may call it a trial, but the actual truth of it is experience. The law of karma and experience — either one the soul wants to give you or the Divine wants to give you or else, it is the law of karma which is giving you the experience. Although the law of karma can be separated from experience, at the same time, karma itself is an experience. So the law of karma may be an experience that God wants to give you or the soul wants to give you.
The third thing that causes things to happen in the human being is will-power. In its purest term, in its highest term, will-power is inner determination. But in ordinary terms it is desire. At its highest, it is the inner urge; at its superficial level, it is an outer, shallow tinkering or wanting. So you can call the third force, will-power or desire.
Lastly there is God’s Vision in Reality and Reality in Vision. God has All-Vision and that Vision is surcharged with Reality. So now these are the four things that affect us: the law of karma, experience, will-power or desire, and God’s Vision in Reality. So there are the four major reasons for things that we see happening in the world.