By my count Alice A. Bailey (AAB) uses the word “incomprehensible” 71 times in her writing that is available on the Lucis Trust website. Most of if not all instances are attributed to Djwhal Khul (DK) whom AAB described as a “Master.” Here are some samples:
This Rod of Power is used at the initiation of the seven Heavenly Men on cosmic levels. It is used also in the initiation of groups, a thing almost incomprehensible to us. Treatise on Cosmic Fire
His subjective life is governed by the Law of Attraction; His material form is governed by the Law of Economy. He is coming under another cosmic law as yet incomprehensible to men, which law is but revealed to the highest initiates. A Treatise on Cosmic Fire
They individualised as the result of work accomplished during incomprehensible aeons of endeavour. A Treatise on Cosmic Fire
This occult abstraction is brought about by an effort of the will at present incomprehensible. A Treatise on Cosmic Fire
The first method of individualisation is that of the third aspect, or latent activity, and follows the line of least resistance under the Law of Economy; the second method is the purely electrical one, and works under the Law of Attraction; whilst the third method lies hidden in dynamic will and is as yet to us impossible and incomprehensible. A Treatise on Cosmic Fire
This should ever be borne in mind. It is to be recognised that much that is written above may seem incomprehensible, but when scientists come to understand and regulate force, that which is written here will become plainer; it will be seen that we have dealt with the positive force in all negative forms above, and including the human kingdom. A Treatise on Cosmic Fire
The system of the Sirian Logos is on the cosmic mental plane, and in a subtle way, incomprehensible to us, our Logos, with His system, forms a part of a still greater Logos. A Treatise on Cosmic Fire
This will necessarily be incomprehensible to you at present for it is not a mediatorship between differences but a fusion of what is already related. Esoteric Astrology
“The Law of Sacrifice and Death is `in a mysterious way’ the reversal of the first law, that of Vibration. It is Vulcan and Neptune in opposition, as yet an incomprehensible idea to us. ” Esoteric Astrology
The causes that we may trace in relation to disease and death are in reality only the working out of certain basic principles which govern—rightly or wrongly, who shall say. —the life of God in form, and they must ever remain incomprehensible to man until such time as he takes the great initiation which is symbolised for us in the Transfiguration. All along in our studies, we shall be dealing with secondary causes and their effects, with the phenomenal results of those subjective effects which emanate from causes too far away for us to grasp. Esoteric Healing
This condition is governed by a cosmic law of rhythm so obscure as to be incomprehensible at this time. Esoteric Psychology
When all the sons of men attain the fifth initiation, He achieves. This is a great mystery and incomprehensible to us. Initiation, Human And Solar
The pain that lies hid in comprehension, not resistance, is felt to the highest circles, yea, it reaches to the Logos Himself. But this is beside the point and well-nigh incomprehensible to you who are yet trammelled by matter. Letters On Occult Meditation
The Mysteries will restore colour and music as they essentially are to the world and do it in such a manner that the creative art of today will be to this new creative art what a child’s building of wooden blocks is to a great cathedral such as Durham or Milan. The Mysteries, when restored, will make real—in a sense incomprehensible to you at present—the nature of religion, the purpose of science and the goal of education. These are not what you think today. Rays and The Initiations
These activities have all been carried on “behind the veil” and are, of course, only a very small part of the total work of the Hierarchy. Much of it would be entirely incomprehensible to you. The Externalisation Of The Hierarchy
His soul and their soul are seen to be identical—potentiality is seen in one, and (from the human standpoint) incomprehensible order leading to ultimate perfection is seen in the other. The Light Of The Soul
This is the basis for the doctrine of Avatars or Divine Messengers. Such an one was the Christ; He was twice an Avatar because He not only struck the keynote of the new age (over two thousand years ago) but He also, in some mysterious and incomprehensible manner, embodied in Himself the divine Principle of Love; He was the first to reveal to men the true nature of God. The invocative cry of humanity (the second of the incentives producing a divine Emergence) is potent in effect because the souls of men, particularly in concerted action, have in them something which is akin to the divine nature of the Avatar. The Reappearance Of The Christ
As far as I know these were all attributed to DK. Again this is only a sampling of the total. From these I draw the inference that DK spent a fair amount of time teaching that his teaching is in many parts incomprehensible to us.