What is the primary purpose of man on earth?

Why is man subjected to earth's trials? What is the fundamental essential for all and why is there no way of having this essential understood by all?

God is an Infinite Spirit or Intelligence, emanating life and love. Intelligence includes all that ever was or will be. 

One of the attributes of intelligence is freedom. 

Each emanation of that Infinite Intelligence partakes of its essence and is endowed with freedom of development and godlike possibilities.

There are many spheres and all eternity in which to perfect this tiny ray of the great Creator.

The mind becomes progressively more the paramount expression of the individual and is able to grasp the meaning and reason of life and the absolute necessity of its free development.