Some Cayce quotes to get you started:
As it has already been given, the Destiny of the Soul is to return to the Giver, the Maker. (262-82)
Then, the Destiny of the Soul - as of all creation - is to be one with Him; continually growing, growing, for that association. What seeth man in nature? What seeth man in those influences that he becomes aware of? Change, ever; change, ever. Man hath termed this evolution, growth, life itself; but it continues to enter. That force, that power which manifests itself in separating - or as separate forces and influences in the earth, continues to enter; and then change; continuing to pour in and out. From whence came it? Whither does it go when it returns? So the Soul's activity in the earth, as it is seen in this or that phase of experience, is that it may be one with the Creative Forces, the Creative Energies. (262-88)
This to some would appear an old, old, soul; yet all souls are as one - they were all of the same; for soul is eternal. (2542-1)
As to commenting upon the subject Destiny of the Soul: As man finds himself in the consciousness of a material world, materiality has often, in the material-minded, blotted out the consciousness of a soul. Man in his former state, or natural state, or permanent consciousness, IS soul. Hence in the beginning all were souls of that creation, with the body as of the Creator - of the spirit forces that make manifest in using same in the various phases or experiences of consciousness for the activity. It has been understood by most of those who have attained to a consciousness of the various presentations of good and evil in manifested forms, as we have indicated, that the prince of this world, Satan, Lucifer, the Devil - as a soul - made those necessities, as it were, of the consciousness in materiality; that man might - or that the soul might - become aware of its separation from the God-force. Hence the continued warring that is ever present in materiality or in the flesh, or the warring - as is termed - between the flesh and the devil, or the warring between those influences of good and evil. As the soul is then a portion of the Divine, it must eventually return to that source from which, of which, it is a part. (262-89)
In that which has been given should be found that necessary for the completion of the lesson, or that portion of same, Destiny of the Soul. The whole theme or the whole purpose in that portion is the awareness of the soul's association in such a manner with infinity in its activity in the finite world, yet in such measures for the soul to know its association and its fulfilling of the purposes. (262-90)
For in patience, as He has given thee, ye become aware of thy soul; thy individuality lost in Him, thy personality shining as that which is motivated by the individuality of thy Lord and thy Master! Thus does the Destiny of the individual lie within self. Thus does the individuality and the Destiny of the soul lie in the keeping of Him who has given Himself in the world that ye through Him might KNOW of everlasting life, become conscious, become aware. For how have His promises read? "Ye abide in me as I abide in the Father, and I will bring to your remembrance those things from the FOUNDATIONS of the EARTH, from the foundations of the world, that ye may be where I AM; and thy glory in my glory, in thy God, shall make of thee that oneness that passeth understanding of men who see only a mental-material consciousness." (849-11)
(Q) Have I karma from any previous existence that should be overcome?
(A) Well that karma be understood, and how it is to be met. For, in various thought - whether considered philosophy or religion, or whether from the more scientific manner of cause and effect - karma is all of these and more.
Rather it may be likened unto a piece of food, whether fish or bread, taken into the system; it is assimilated by the organs of digestion, and then those elements that are gathered from same are, made into the forces that flow through the body, giving the strength and vitality to an animate object, or being, or body.
So, in experiences of a soul, in a body, in an experience in the earth. Its thoughts make for that upon which the soul feeds, as do the activities that are carried on from the thought of the period make for the ability, of retaining or maintaining the active force or active principle of the thought THROUGH the experience.
Then, the soul re-entering into a body under a different environ either makes for the expending of that it has made through the experience in the sojourn in a form that is called in some religions as destiny of the soul, in another philosophy that which has been builded must be met in some way or manner, or in the more scientific manner that a certain cause produces a certain effect.
Hence we see that karma is ALL of these and more. What more? Ever since the entering of spirit and soul into matter there has been a way of redemption for the soul, to make an association and a connection with the Creator, THROUGH the love FOR the Creator that is in its experience. Hence THIS, too, must be taken into consideration; that karma may mean the development FOR SELF - and must be met in that way and manner, or it may mean that which has been acted upon by the cleansing influences of the way and manner through which the soul, the mind-soul, or the soul-mind is purified, or to be purified, or purifies itself, and hence those changes come about - and some people term it "Lady Luck" or "The body is born under a lucky star." It's what the soul-mind has done ABOUT the source of redemption of the soul! Or it may be yet that of cause and effect, as related to the soul, the mind, the spirit, the body. (440-5)