13. But the soul, in the early phases of its existence, is like a child, lacking experience; it is, therefore, subject to error. God does not give the soul experience, but God gives it the means of acquiring experience; every false step taken by the soul on the road of evil, keeps it back; it undergoes the consequences of this delay, but it is by means of those consequences that it learns, at its own expense, what it must avoid. It is thus that, little by little, the soul acquires development, effects its own improvement, and advances in the spiritual hierarchy, until it has reached the state of fully purified Spirit or Angel. The angels, then, are the souls of human beings who have reached the highest degree of perfection attainable by created existences, and who have entered upon the full enjoyment of the felicity for which they were created. Before attaining to the supreme degree, they enjoy degrees of happiness proportioned to their degree of advancement, but their happiness is never that of idleness, as it consists in the functions to which they are called by the Almighty and which they rejoice to discharge, because the occupations of spirits are, for them, a means of progressing.