All known references to the Law of Karmic Liability by Alice A. Bailey (AAB) in her voluminous writings and those given to her by Djwhal Khul (DK). Links on these pages of the Laws of Alice A. Bailey are to the online books at the Lucis Trust website.
What is a law?
… a law is but the spiritual impulse, incentive and life manifestation of that Being in which he lives and moves. A Treatise on White Magic , INTRODUCTORY REMARKS
A law is an expression or manifestation of force applied, under the power of thought, by a thinker or group of thinkers. Discipleship in the New Age, Vol. I , SECTION ONE – DISCIPLESHIP IN THE NEW AGE – Part 2
… a law is in reality the effect of the life of a greater entity as it encloses a lesser within its living processes. Esoteric Healing , Part Three – The Fundamental Laws of Healing
… a law is but the effect of the continued intelligent activity of the Life aspect as it works in conjunction with matter. Esoteric Psychology – Volume I , 5. The Rays in Cyclic Manifestation
A law is only an expression or manifestation of force, applied under the power of thought by a thinker or group of thinkers. Esoteric Psychology – Volume II , II. The Seven Laws of Soul or Group Life – Part 5
A law presupposes a superior being who, gifted with purpose, and aided by intelligence, is so coordinating his forces that a plan is being sequentially and steadily matured. A Treatise on White Magic
Quotes I found below:
Therefore the use of the term “immortality” infers timelessness and teaches that this timelessness exists for that which is not perishable or conditioned by time. This is a statement requiring careful consideration. Man reincarnates under no time urge. He incarnates under the demands of karmic liability, under the pull of that which he, as a soul, has initiated, and because of a sensed need to fulfill instituted obligations; he incarnates also from a sense of responsibility and to meet requirements which an earlier breaking of the laws governing right human relations have  imposed upon him. When these requirements, soul necessities, experiences and responsibilities have all been met, he enters permanently “into the clear cold light of love and life” and no longer needs (as far as he himself is concerned the nursery stage of soul experience on earth. He is free from karmic impositions in the three worlds, but is still under the impulse of karmic necessity which exacts from him the last possible ounces of service that he is in a position to render to those still under the Law of Karmic Liability. You have, therefore, three aspects of the Law of Karma, as it affects the principle of rebirth:
1. The Law of Karmic Liability, governing life in the three worlds of human evolution, and which is ended altogether at the fourth initiation.
3. The Process of Integration, dealing with the period wherein the liberated soul again becomes conscious of itself as the Angel of the Presence and is reabsorbed into the world of souls, thus entering into a state of reflection. Later, under the impact of  the Law of Karmic Liability or Necessity, the soul again prepares itself for another descent into form.
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