Qabalah.  [Heb.]  "The tradition of secret wisdom of the Hebrews."  See ["Liber LVIII" and Appendix V infra].

Liber ABA (Book 4):  Magick, Glossary

Of the methods of increasing Understanding those of the Holy Qabalah are perhaps the best, provided that the intellect is thoroughly awake to their absurdity, and never allows itself to be convinced.

Liber ABA (Book 4):  Magick, Part II:  Magick (Elementary Theory), Cap. VII:  The Cup

This is a very simple subject, and presents no difficulties to the ordinary intelligent mind.

The Book of Thoth, Part I, The Theory of the Tarot, Section II, The Tarot and the Holy Qabalah)

...The work of every explorer...is immensely helped by a grasp of general principles.  Every Magician, therefore, should study the Holy Qabalah."

Liber ABA (Book 4):  Magick, Part III:  Magick in Theory and Practice, Cap. 0:  The Magical Theory of the Universe

The Qabalah maps ourselves by means of a convention.

Liber ABA (Book 4):  Magick, Appendix III:  Notes for an Astral Atlas

Now there is a traditional correspondence, which modern experiment has shown to be fairly reliable.  There is a certain natural connection between certain letters, words, numbers, gestures, shapes, perfumes and so on....  These correspondences have been elaborately mapped in the book 777 in a very convenient and compendious form.  It will be necessary for the student to make a careful study of this book....

Liber ABA (Book 4):  Magick, Part III:  Magick in Theory and Practice, Cap. 0:  The Magical Theory of the Universe

Now you must learn Qabalah.  Learn this Alphabet of Magick.  You must take it on trust, as a child does his own alphabet.  No one has ever found out why the order of the letters is what it is.  Probably there isn't any answer.

Magick without Tears, Cap. IV:  The Qabalah: The Best Training for Memory

The Holy Qabalah, based as it is on pure number, evidently possesses an infinite number of symbols.  Its scope is conterminous with existence itself, and it lacks nothing in precision, purity, or indeed in any other perfection.  But it cannot be taught [It is easy to teach the general principles of exegesis, and the main doctrines.  There is a vast body of knowledge common to all cases; but this is no more than the basis on which the student must erect his original research.]; each man must select for himself the materials for the main structure of his system.  It requires years of work to erect a worthy building.  Such a building is never finished; every day spent on it adds new ornaments.  The Qabalah is therefore a living Temple of the Holy Ghost.  It is the man himself and his Universe expressed in terms of thought whose language is so rich that even the letters of its alphabet have no limit.  This system is so sublime that it is unsuited to the solution of the petty puzzles of our earthly existence. In the light of the Qabalah, the shadows of transitory things are instantly banished.

Liber ABA (Book 4):  Magick, Part II:  Magick (Elementary Theory), Cap. XVIII:  Concerning Divination

In order to understand thoroughly the Key Scale, the student should have mastered "An Article on the Qabalah," [["Liber 58,"] The Equinox I(5), pp. 72-89 [and in 777 and Other Qabalistic Writings].] and acquainted himself with the use of "Liber D." [The Equinox I(8), Supplement [and in 777 and Other Qabalistic Writings].]

Liber ABA (Book 4):  Magick, Appendix V:  A Few of the Principal Correspondences of the Qabalah

The Tree of Life has got to be learnt by heart; you must know it backwards, forwards, sideways, and upside down; it must become the automatic background of all your thinking.  You must keep on hanging everything that comes your way upon its proper bough.

At first, of course, all this is dreadfully confusing; but persist, and a time will come when all the odd bits fit into the jig-saw, and you behold--with what adoring wonder!--the marvellous beauty and symmetry of the Qabalistic system.

And then--what a weapon you will have forged!

What power to analyze, to order, to manipulate your thinking!

...When you are a real adept at all these well-known calculations 'prepare to enter the Immeasurable Region' and dig out the Unknown.

...In the course of a few years, you should have built yourself a Palace of Ineffable Glory, a Garden of Indescribable Delight.  Nor Time nor Fate can tame those tranquil towers, those Minarets of Music, or fade one blossom in those avenues of Perfume!

Magick without Tears, Cap. IV:  The Qabalah: The Best Training for Memory