"Love and Wisdom are the essential factors of Immortal Life"
“To the question so often asked as to why we are here, why man must pass through experiences, some of which seem heart-rending, the answer is plain: Without some such experience there could be no Life, there could be no Love, and there could be no Wisdom.
We cannot perceive the light, except we have had experience with varying
degrees of its intensity; and if we have had some experience with darkness, we the more readily appreciate the light. We can have no knowledge of the good, unless we have had some experience with that which is less good; and if we have had some experience with that which we call evil, the good is the more appreciated. Sweetness, to the sense
Why are we here?
What is the reason for a human body?
How are we created? – The Cycle of Necessity maps out the soul's journey through time. Before its commencement (differentiation), time was not. But having embarked on its long and wearisome journey, the two soul's of the one Divine Ego, descend into matter and then, carried on the life wave, ascend back up, evolving through the countless forms available in the mineral, vegetable and animal realms. Eventually the form of human is attracted where in one
lifetime the culmination of the soul's journey into matter is attained. It is also when, as humans, we can develop self-consciousness. The twin souls were called forth from the Source of All because of a developing Cosmic Need and are being trained to fulfill a unique role within God's Great Plan. (see Finding One's Cosmic Work Chapter 1 in Course 14 Occultism Applied to Daily Life.) .
"If, therefore, the soul is to develop its powers, there is no means that we can imagine which would be so effective as its association with the various forms of the physical, the astral, and the spiritual worlds."
Elbert Benjamine
"Love and Wisdom are the essential factors of Immortal Life"
of taste, is only perceived by comparison with things less sweet. It takes the sour,
such as lemon, to bring out in proper contrast the sweetness of honey. In fact, the wider the range of experience the clearer the perception of qualities and values. Without some such experiences with form as we are familiar with there would be no life, no consciousness, no knowledge, no love. It is impossible to imagine how life, wisdom, and love could be developed, or could exist, without some such chain of experiences as those with which we are familiar.  
As to the why of existence itself, that is, the why of the potentiality manifesting through the universe of form, we are not called upon to explain it. We cannot conceive of a condition in which existence is lacking, nor have we had any experience that suggests such a condition ever was possible. It is quite enough, then, for the human mind to attempt to explain how existence acts and is conditioned, without attempting to commence from nothingness, which is logically impossible, and show how all that exists was derived from this unthinkable, impossible, abstraction. But if we commence with a potentiality, such as the ego undoubtedly is, it is not difficult to trace the steps by which the soul must have gradually developed until it finally functions through the body of man.
As I have already shown in some detail, the attractive power that for convenience I call Love and the consciousness that for convenience I call Wisdom, are developed only through experience with form. I mean here that all activity and life are due to the principle of attraction which to generalize I refer to as Love, and that consciousness results from the activities so engendered. Such consciousness, in all its forms, I generalize under the term Wisdom. Furthermore, the feeling of attraction and the consciousness are intensified in proportion to the contrasts in experience. For instance, if we have just tasted something sweet, we are the more conscious of, and the more repelled by, the taste of something bitter. In fact, the
wider the contrast is between experiences, the stronger they tend to impress themselves upon  consciousness and the stronger they attract or repel. And the more varied the experience, the more shades of consciousness, the more discrimination possible; and the more shades of feeling, the wider the sensations and emotions.  
Therefore, if the soul is to develop power; which depends upon its strength to attract and repel, upon Love; and if it is to develop knowledge, and not remain
semi-conscious, it must have experiences of as wide contrast and of as great variety as possible. Contrast means strong impressions and strong desires. Variety means
“The greatest contrast of which we know is that between spirit, or still finer substance, and matter.”
discrimination and fine shades of feeling. A creature without these is not alive in the full sense that man is alive.  
The greatest contrast of which we know is that between spirit, or still finer substance, and matter. And the greatest variety of which we know is the countless forms on the physical, the astral, and the spiritual planes.  
If, therefore, the soul is to develop its powers, there is no means that we can imagine which would be so effective as its association with the various forms of the physical, the astral, and the spiritual worlds; for these forms offer the widest possible contrast of which it is possible to conceive. They, therefore, offer the greatest opportunity to develop the attributes of attraction and repulsion; the greatest opportunity to develop feeling, to develop that which becomes Love.
And if the soul is to develop discrimination, there is no means that we can imagine which would be so effective as its association with the various forms of the physical, the astral, and the spiritual worlds; for these forms offer the widest possible variety of which it is possible to conceive. They, therefore, offer the greatest
"Love and Wisdom are the essential factors of Immortal Life"
opportunity to develop the attributes of perception and comparison; the greatest opportunity to develop knowledge; to develop that which becomes Wisdom.  
That the soul may acquire Self-Consciousness it must attain Wisdom. Life, however, depends also upon love; for love is the power that attracts and holds together whatever form the soul occupies. If the soul is to be immortal it must develop sufficient love, sufficient attractive power, to build such forms as are necessary for its
imperishable existence. Love and Wisdom are the essential factors of Immortal Life.  
Because there is no conceivable way by which the soul can acquire love and wisdom except through varied experiences in form, the cycle through which the soul passes, from spirit to matter and from matter back to spirit; living in countless forms in each
of the three realms; is called by initiates, "The Cycle of Necessity." That is, this cycle of experiences in various forms is a necessity if the soul is to acquire the love and wisdom which alone make possible Self-Conscious Immortality. The mission of the soul, therefore, is to acquire Love and Wisdom to the end that Self-Conscious Immortality may be attained.

The Cycle of Necessity
Now let us trace the soul in its Cycle of Necessity. It is first differentiated in the
highest state of the spiritual realm. It then possesses neither consciousness nor
feeling; but is supplied by the ego with energy, and by the ego is given a specific trend. This specific trend is determined by the love vibrations of its angelic parents that brought about the ego's differentiation. That is, such ego with its two souls is a part of
universal society, differing from all other egos. In universal society, as in all meritorious organizations, there is division of labor. Nature moves toward specialization, each specialized part performing a definite function. Therefore, the soul impelled on its cyclic journey is given that trend which offers it the opportunity to develop such attributes as it requires if it is ultimately to fill its proper sphere as a useful member in the cosmos.
It therefore attracts about itself, as the result of the energy supplied it by the ego, a form of spiritual substance of the highest state. Its experiences in this form give it some slight consciousness; being energy, when it repels the present form gives it additional power to attract another form of slightly greater complexity. Its experiences in the second form give it the consciousness, and the attractive ability, later to attract a third spiritual form of higher complexity still.
Its attractive power and its subjective consciousness increasing, it gradually gains the ability to attract forms of grosser spiritual substance; and after much experience living subjective lives in the lowest grade of spiritual substance, it finally gains the power to draw about itself an astral form. This process continues in the astral realm.
These forms inhabited on the astral plane are termed elementals. As soon as the
experiences in one astral form have been assimilated, this form is repelled and the
organizations of energy thus gained enabled it to attract a still more complex, and a still more dense form, until finally a time is reached when the soul has enough energy, or love power at its command, as the result of its experiences in spiritual and astral forms, to enable it to attract about itself a physical form. This is the first objective experience; it becomes incarnated in a mineral.  
The mineral form of life is the lowest rung on this Jacob's Ladder by which the soul descends from, and ascends to, heaven. Carried on the mineral life wave it enters the zone of the planet where its first expression of external life is to be experienced. By its power of love, which is the outcome of its
“The mineral form of life is the lowest rung on this Jacob's Ladder by which the soul descends from, and ascends to, heaven.”
"Love and Wisdom are the essential factors of Immortal Life"
“So, in the seventh evolutionary state from its commencement, the soul
undergoing the Cycle of Necessity attains the estate of manhood…”
experiences upon the descending arc of its cycle, it attracts to itself the attributes which constitute a crystal of matter. This initial crystal is the simplest form of mineral. The attributes expressed by it are due to the polarizing power of the soul.
After undergoing its cycle of life in the form of the lowest mineral, the soul begins to lose affinity with it, and finally, as the result of repulsion, passes into the astral realms. The mineral is dead. After a period of astral life, however, the soul, by the power of its accumulated love, attracts a new form and undergoes incarnation; this time in a mineral a step higher in the scale of evolution. Having reaped and recorded the experiences of one form, the soul is impelled, by the restless ego in search of wisdom, to exert its power to attract and mold a higher and more complex form. Thus it evolves, step by step, in its first evolutionary state, through the various kinds of mineral life.  
From the highest mineral form, the monad is carried into the astral zones
corresponding in astrological quality to the next planet of the septenary chain, there to undergo a period of subjective life. This is the second evolutionary state. Finally it is carried forward by the life wave and becomes incarnated, as its third evolutionary state corresponding to the next planet, in the vegetable kingdom. Here the action of love and wisdom evolves it still more rapidly by means of successive births and deaths. The lowly lichen forms but a step, and as it dies the soul, by its inherent power
of love, attracts to itself a higher form of plant life, evolving rung upon rung on the ladder of evolution, ever attracting, evolving, and perfecting forms for more perfect and complex expression; and finally repelling them for those still higher in the gamut, until at last it blooms as the blushing rose.
From the highest type of plant life the evolutionary life wave of the solar system carries the impersonal monad to its fourth evolutionary state, astrologically corresponding to the next planet of the
septenary, to undergo another cycle of assimilation in the astral spheres. Thence, after a period of subjective gestation, it passes to the fifth evolutionary state, corresponding astrologically to the next planet, to enter what has now become the animal life wave. Through attraction, or love, the soul becomes incarnated in the lowest form of animal life. Through love, which is the expression of accumulated wisdom, it molds the form it temporarily occupies. Then, after its cycle of experience in this form, the animal dies, and the soul, having more complex
needs, or desires, attracts to itself a still more complex form, evolving, through the power of love, or desire, this form to meet as nearly as possible the requirements of its environment.
Having exhausted the realms of animal life, and ever impelled by the restless energy of its ego to seek new and more complex experiences, it passes from the region of its animal experiences to undergo another period of subjective assimilation in the astral spheres, the sixth evolutionary state, corresponding astrologically to the next planet in the septenary; thence onward to the seventh evolutionary state, in which it reaches the climax of incarnated perfection.  
In the scheme of universal law the seventh state is always that of action and completion insofar as expression is concerned. The seventh condition is always a synthesis of the six preceding, and constitutes the point of transition to a new octave of existence. So, in the seventh evolutionary state from its commencement, the soul
undergoing the Cycle of Necessity attains the estate of manhood, where it recapitulates in a single life all the various states through which it has passed, and attracts to itself the perfect form which has an exact correspondence to
"Love and Wisdom are the essential factors of Immortal Life"
every plane, state, and center of life in the universe.  
At this point in its journey, for the first time, and as the result of the accumulated impersonal wisdom gathered through the power of love, or attraction, it becomes self-conscious. It is no longer an impersonal being
impelled forward by inner and to it unaccountable yearnings. It is now a self-conscious entity endowed with all the responsibility of a morally free agent; a responsibility varying in individual cases, being proportional to the ability and the opportunity”