As the man learns how to use his free-will, more and more of it is entrusted to him, so that he can acquire for himself practically unbounded freedom in the direction of good, but his power to do wrong is strictly restricted.

He can progress as rapidly as he will, but he cannot wreck his life in his ignorance.

In the earlier stages of the savage life of primitive man it is natural that there should be on the whole more of evil than of good, and if the entire result of his actions came at once upon a man as yet so little developed, it might well crush the newly evolved powers which are still so feeble.
Besides this, the effects of his actions are varied in character.

While some of them produce immediate results, others need much more time for their action, and so it comes to pass that as the man develops he has above him a hovering cloud of undischarged results, some of them good, some of them bad.

Out of this mass (which we may regard for purposes of analogy much as though it were a debt owing to the powers of Nature) a certain amount falls due in each of his successive births; and that amount, so assigned, may be thought of as the man's destiny for that particular life.
All that it means is that a certain amount of joy and a certain amount of suffering are due to him, and will unavoidably happen to him; how he will meet this destiny and what use he will make of it, that is left entirely to his own option.