Another (edited) passage from Schaya, published here for future reference:

Malkhut, the ‘lower mother’, is from the cosmological point of view what Binah, the ‘highest mother’, is from the ontological point of view; like the latter, she is on the one hand the ‘mirror’ and on the other the ‘prism’ of divine emanation. On the one side she sends back to the ‘king’, Tif’eret, all the radiation she receives from him through the intermediary of his act, Yesod; and she is thus eternally united with him, her “husband”, who in turn is infinitely united with the ‘supreme crown’, Keter Elyon. On the other side she projects the influx of the ‘king’ out from the causal or Sefirotic unity and thereby creates the cosmos; and in her cosmic manifestation she herself ‘descends, as immanence, into the created being in order to connect him with his transcendental source.

However, in considering these attributes and principal modes of activity of Malkhut, we have not yet answered the question as to what it is as substance. Now it is not a distinct substance, but rather the undifferentiated, uncreated principle of all substance which in no way emerges from the infinite and indivisible unity of the creative causes: this principle envelopes them and is yet hidden within them, like ‘very pure and imperceptible air. What is this ‘air’ which is not breathable in the same way as the air which surrounds us? It is avir, the universal ‘ether’, the quintessence of the four subtle or celestial elements and of the four corporeal or terrestrial elements. And what is the ether itself? It is none other than the infinite receptivity of the divine ‘intelligence’: Binah. ‘The father (Chokhmah) is the spirit hidden in the “Ancient of days” (Keter) in whom this “very pure air” (identical with Binah) is enclosed.’ The universal ether envelopes the intelligible emanation of Chokhmah from the moment of its first emergence from the ‘ancient of days: ‘it unites with the (spiritual) flame issuing from the (supreme) and brilliant lamp’ and follows it in the whole course of its descent towards cosmic possibility and throughout the cosmos itself.

‘Above’, the ether is the infinite receptivity of Binah, by virtue of which God reveals himself to himself; ‘below’, it is the cosmic receptivity of Malkhut, which becomes concrete in creative substance. In other words, that which is pure receptivity in Binah and creative contraction in Din [Gevurah] becomes cosmic emptiness in Hod and finally undifferentiated and causal substance in Malkhut. This process of principial ‘substantialization’ has its positive point of departure in Chokhmah, whose luminous plenitude is manifested by Chesed, and which, having received its universal form from Tif’eret, is manifested by Netsach as the life of the worlds, which Yesod communicates to Malkhut, the substance.

In this way, all the Sefirot descend’ from Keter, in perfect co-emanation and co-operation, and are finally concentrated in Malkhut and manifested by Malkhut in the cosmic mode.

However, as we have seen, if one wishes to remain close to pure and superintelligible truth, there can be no question of anything having emanated or being distinct from the supreme, the only reality, the ‘One without a second’.

I have been looking for a structural account of the Sefirot, analogous to the obscure relationship between the typological description of Jungian/MBTI and the Jungian functions which combine to produce typological effects, or the yaos of the double-trigrams that combine in the hexagram descriptions of the I Ching. I’ll need to return to this and study it closely.