Warning: this review is rife with spoilers.
I told Melanie that I both disliked and kind of loved this book.
First, let us deal with the dislike. While the host of characters were distinct enough beforehand, beside some teasing obsequiousness toward Jubal, they to a one became hive-mind lobotomy patients the moment they joined up with the Church of All Worlds. Ben's transition from Doubting Thomas to True Believer happened off-stage and was based on little more than Jubal telling him to examine his prejudices. Parts of the novel reads as a treatise on why polyamory is the only reasonable and civilized course of action and, possibly, will give one superpowers. The story is uneven and feels rushed in the latter third, where we actually are more fully dealing with the title character. The only real "threat" presents itself in the last twenty pages (and I am not referring here to the Fosterites but that the Martian Old Ones had been using Michael as a spy and might make Earth cease to be because we are emotional/not necromancers). From the moment Michael shows any initiative toward spirituality, it is clear that he is a Christ figure and will therefore be a corpse before the end of the book, which further disinclines the reader to having any attachment or investment in an already disconnected character. Much of the potential intrigue in the beginning of the novel is forgotten almost immediately, as though it happened in another book entirely. There are nothing but easy answers (Jubal says something clever, no one questions it, governments bow to him; Michael waves his hand and anything dangerous vanishes, which does mean mass murder with no punishment). The lack of consequences extends even for Michael's martyrdom, since he is an archangel in the last chapter and most all of the characters accept this with the placidity of cows. It is Heinlein and so can safely be assumed to be written well, though it feels like three or four novels squeezed together into one and not without some inconsistencies in mood.
Now that I have irritated the many fans of this classic, here is why I kind of loved it. Some of the ideas in it were beautiful, such that I find it totally reasonable that it inspired a real Pagan church (even though the novel more than implies Judaism/Christianity/Islam must be right because these religions acknowledge Archangels). I have found myself so fond of the word "grok" (which I had used prior to reading this book and which is in the Oxford English Dictionary) that I have to actively not use it. Jubal is a compelling character, frankly the only one who I cared about by the end. It reignited my interest in psycholinguistics, how language affects thought, such that Melanie got me the book The Stuff of Thought as a birthday present. The tone is light enough that the novel's heavier thoughts go down without struggle.
I get the feeling that Heinlein contrived the philosophy for the Church of All Worlds and wrote a novel to surround it, occasionally with some clumsiness. Though easily dismissed as a variant of hippy free love, the idea of growing closer, of having a total intimacy with other people is lovely. Unrealistic, but lovely. The fault is more with the limits of reality and the cynicism of human relationships, though I have to admit to an adamant urge to call Jinx and inform her that I wanted to share water with her. However, that is the extent of fluids I care to share with anyone outside of Melanie, no matter how limited and puritanical Heinlein's novel implies that is. And it isn't that my body can't instantly heal from diseases (see: superpowers) but because I am keenly aware that growing closer with everyone dilutes the growing closest with one. When the crux of your work is ideas, one had better be sure to make them credible enough that they can perpetuate the suspension of disbelief.