It is the heart (soul) we must understand to find out why we suffer or have joy in our lives. The following is from the Ofudesaki, the most sacred scripture in the world.

Until now, whatever occurrence/matter was about the world (can get away if no one sees you do it).

From now on you will understand what comes forth from the innermost heart   Ofudesaki 3-47

Interpretation:

God is telling us the worldly path is where one can get away with evil as long as no one sees you doing it, or where one doesn’t care if anyone sees it.  The path of the heart is where your heart brings upon suffering for what you have done in the past. It is not God that punishes us, but it is our own hearts punishing us. We reap what we have sowed.