This line, as usual, mey be read at many different levels.
The first, plain one is the description of the Task that thw Beast and the Scarlet Woman are called to perform; AC calls himself the Beast 666, so he is claiming the title for himself; then in the commentaries he explains how many different women during his life have covered the role of the Scarlet Woman.
Even tho he changes so many of them, he still says that all the power of the Beast is given unto the SW.
This makes me think: on one side AC is one that wouldn't think twice to strip the title from one to give it to the next; on the other side he doesn't say that the power is in him; the power is still in the SWs.
This highlights how 2=0: he needs a counterpart to his energy to annihilate them both and get back into Nuit.
I think we don't go wrong up to here.
As for the manifestation of the Beast and the SW, I have kind of wrapped my mind around it like this:
Nuit and Hadit are the archetypal energies of masculine and feminine in Atziluth.
Beast and Scarlet Woman as we see them in the Lust card are their emanations in Briah.
But AC attributes the titles to himself and some of his companions, taking them in the phisical reality of Assiah. What happens at Yetzirah level, then?
I think that the title is to be passed down, but I am not sure that the present Thelemic community have a Beast and a Scarlet woman in charge.
It could be that when a priest and priestess achieve access to yetzirahtic states of consciousness through K&C of HGA, then they may claim the titles for themselves and get on with the task of gathering people and spreading the word of Thelema.
Like they attain a level of consciousness that allow them to start their own group?
I may be way wrong here, but I would like to understand..
I want to make clear that this is just my opinion, I am writing down what I think to ask if I am right, and get corrected if I am wrong.
Thanks to everyone for helping me through the discovery of this beautiful book.