Abraham Abulafia on Performing Letter Permutations

"We learned from the divine, prophetic, and religious Kabbalah that when the wise mystic performs the Tzerufim (Permutations), the Ruach haKodesh (Holy Spirit) rests upon him. At first, the things he obtains from the Tzeruf will fill him with fear and awe; his hair will stand on end, and his organs will tremble. Then, if he is worthy, Ruach Elohim (Spirit of God) will rest upon him. He will feel as if his entire body from head to toe, were anointed with anointing oil. He will become the anointed of haShem (the Name), and become his emissary; he will be called the Malakh haElohim (Angel of God) and his name will be the name of his Rav (Master), which is Shaddai (Almighty), who is called Metatron, the Prince of the Presence (Sar haPanim)."

-- Abraham Abulafia, Chaye haOlam haBa (Life in the World to Come)

Tishby on the Torah's Fundemantal Nature

"When the kabbalist comes to assess the Torah's fundamental nature, its hidden mystery, he does not see it as a collection of commandments, statutes, and ordinances, of ethical pronouncements and accounts of historical events, all proceeding from the mouth of God. It is for him a massive treasury of divine forces and divine lights that have donned the form of letters and words and so revealed themselves in the book of the Torah."

-- Isaiah Tishby, Wisdom of the Zohar p. 283

Sefer haZohar on the Holiness of Words of Torah

"Rabbi El'azar opened, 'If you are wise, you are wise for yourself; if you scoff, you alone will suffer' (Mishlei 9:12). Woe to the wicked of the world who neither know nor consider words of Torah! And if they do not consider, words of Torah appear to them entirely empty and worthless, since they lack intelligence. All because they are empty-headed! For all words of Torah are entirely precious. Of every single word is written: 'She is more precious than rubies; nothing desired can compare with her' (ibid. 3:15, 8:11) ─ with words of Torah.

"All those close-minded, close-hearted fools, upon seeing words of Torah ─ as if it weren't bad enough that they are unaware, they actually claim that those words are defective, worthless! Woe to them when the Blessed Holy One avenges the humiliation of Torah and they are inflicted with punishment for rebelling against their Lord!

"What is written in Torah? 'It is not an empty word מכם (mi-kem), for you' (Devarim 32:47); and if it is empty, it is mi-kem, from you ─ because of you! For Torah is completely filled with all precious stones and priceless pearls, with all the world's treasures, as is said: 'Nothing desired can compare with her'. So how can they say she is empty?

"King Solomon declared, 'If you are wise, you are wise for yourself', because when a person grows wise in Torah, this is his own benefit, since to Torah herself he cannot add even a single letter. 'If you scoff, you alone will suffer', for he will not diminish the glory of Torah in the least. His scoffing is totally his, lingering within him to eliminate him from this world and from the world that is coming.

"Come and see: When supernal letters all combine on this rung ─ last of all sacred supernal rungs, filled by them, blessed by the higher world ─ then this rung stands poised to water all those flocks, each one fittingly, each one watered with judgment and compassion."

-- Sefer haZohar 1:163a (transl. D. Matt)

The last paragraph is an allusion to letter combination and permutation methods of mystical meditation, as taught for example by the school of Rabbi Abraham Abulafia. The "last rung" is a reference to the 10th sefirah, Malkut.

Moshe Eliaqim Beriah on Combination of Letters in Sefer Yetzirah

"It is written in Sefer Yetzirah that the letters are called stones and the words are called houses. And the person who approaches the study of Torah and prayer, ought to build a house, which is the combinations of letters, filled by illumination and perfection and to prepare a Tabernacle for God, Blessed be He, to dwell there in those words of the prayer."

-- Moshe Eliaqim Beriah, Qohelet Moshe 8a (1875)

Rabbi Moshe Cordovero on the Letters of Emanation and Performing Mitzvot

"There is no doubt that the letters that compose each and every pericope of the Torah, and every Gemara and chapter someone is studying, which concern a certain Mizvah, have a spiritual reality which ascends and clings to the branches of a certain sefirah, namely the sefirah that hints to this Mizvah, and when the person studies the corresponding Mizvah or the chapter or the pericope or the verse, those letters will move and stir on high.

"And behold, the voices and the realities of the letters produced by the twist of the lips bestow on them a certain act and movement like that of a body. And the reality of the letters ascends and it is found everywhere on the way of their ascent from one aspect to another, following the way of the descending emanation from one stage to another."

-- Rabbi Moshe Cordovero, Or Yaqar vol. 12 p. 147 (transl. Idel in "Reification of Language in Jewish Mysticism" 1992)