What is the meaning of energy development?

All growth proceeds in the dark. 

This is according to law. 

Were any soul given power to watch his―or her development at each instant of its procedure, interest in self would draw off most of the energy necessary for development. 

That is perhaps why we cannot see―or remember our personal past―it would deflect energy needed elsewhere, while on the spiritual side of life, spirit can see, recall and assimilate what their past has built. 

Then they apprehend just what they lack to balance their character, and with strong conviction, as to the remedying of this lack, they stamp their inborn new self at the instant of rebirth, so that they are bom with conviction of duty along lines they themselves have previously studied out.

Each newborn human is given a certain impetus along lines it desires to travel―or develop. 

If from ignorance―or other cause, that push was not sufficiently strong to propel itself forward far enough, then its guardians and friends help it to fulfill its destiny as planned.