Some people cringe at my occasional reference to a Thelemite practicing Christianity but, truth is, I know such folks.

I really think it goes back to the line I quoted in another thread (on polytheism/monotheism) the other day: "Should therefore the candidate hear the name of any God, let him not rashly assume that it refers to any known God, save only the God known to himself."

93 93/93

Monotheistic systems tend to express their Monad in highly diverse expressions - which I've never been able to distinguish from "multiple gods."

And every polytheistic system I know ultimately recognizes a singular, transcendant idea above the diversity.

Our core scripture lists multiple distinctive god-names. At the same time, Nuit, the goddess who is the whole of space, is understood to be the whole of everything - any other idea is an aspect of her infinite diversity.

Comme si, comme ca.

"
PS - But if you were wondering if she is distinctively honored in Thelema, I'd have to answer no - because pretty much all deities are accepted as "just another way to find the One.""

Now it sounds like you are really monotheists.

"Is the Goddess Isis honored in Thelema? Are there any Thelemic rituals to her, or any Thelemic holy texts that mention her?"

Honored in many ways, yes.

There are some private rituals that Crowley wrote with focus on her. She's one of three primary presences in the A.'.A'. First Order initiation ritual.

She's implicitly mentioned in Liber Legis 1:22: "Now, therefore, I am known to ye by my name Nuit, and to him by a secret name which I will give him when at last he knoweth me. Since I am Infinite Space, and the Infinite Stars thereof, do ye also thus. Bind nothing! Let there be no difference made among you between any one thing & any other thing; for thereby there cometh hurt." Note the capitaliation in the second sentence, which often is taken as one level of decipherment of the first sentence.

Her form and energy are the astral formulation of one important officer in Temple of Thelema rituals.

Though this isn't exactly a comment on her place in Thelema per se, it's worth noting that the Los Angeles lodge of Aspirants to Light is called Isis Lodge.

PS - But if you were wondering if she is distinctively honored in Thelema, I'd have to answer no - because pretty much all deities are accepted as "just another way to find the One."