Tori Amos is more than a pop star. She is a religion. Ever since the release of her solo debut, “Little Earthquakes,” in 1991, the redheaded pianist has amassed a rabid international following obsessed with the complexities of her music. For these fans, the publication of “Tori Amos: Piece by Piece” (Broadway Books, 368 pages, $23.95) is akin to the discovery of the Dead Sea Scrolls (or, to reference another mysterious musician worshipped as a deity, the publication of Bob Dylan’s “Chronicles, Volume One.”) Written by Amos in collaboration with veteran music journalist Ann Powers, the book is far from a typical rock tell-all.

“Tori Amos is not your ordinary girl, but she has much to say to all of us interested in what it means to be a woman, a creator, a nurturer, a fighter, a part of all the universes that merge into a life,” Powers writes in the preface. “Piece by Piece” explores these different facets of Amos’s existence using mythology from cultures around the world: the Native American Corn Mother helps navigate family history; Mary Magdalene oversees the spiritual and the erotic; Dionysus informs rock and roll’s ecstatic release, et cetera. Each chapter also features “song canvases” explaining the inspiration behind various “song children,” as Amos calls them.

The story of Amos’s forty-one years is told in a non-linear fashion. Her experiences growing up in a household headed by a Methodist minister father are related to the way she navigates being a professional touring musician with raising her daughter, Natashya. A struggle with her record label in the late 1990s recalls her ill-fated first attempt to break into the industry as a hair-metal siren a decade earlier. Certain episodes are frustratingly glossed over, namely the rape that inspired the terrifying “Me and a Gun” from “Little Earthquakes,” and Amos’s involvement with the Rape, Abuse & Incest National Network, which she co-founded in 1994. Others are recounted in painful detail, such as the series of miscarriages Amos suffered before giving birth to Natashya in 2000. Throughout it all, Amos turns to her piano to help her make sense of what’s going on around and inside her. “Music more than anything else is what keeps me on the planet,” she writes.

Although “Piece by Piece” offers much sage advice concerning the evils of the music business, as well as plenty of guidance for those seeking to come to terms with their own creativity, the book ultimately succeeds as little more than a sacred text for Toriphiles. Those who dismiss Amos as a hippie-dippy new age space cadet won’t sit through 368 pages of philosophizing, while casual fans might balk at in-depth analyses of Amos’s diet, shoe collection, set lists, and lighting design. It’s heartening to know that she puts so much time and effort into what seem to be minor matters, but it’s also difficult to care.

Like “Piece by Piece,” Tori Amos’s ninth album, “The Beekeeper” (Epic), is unlikely to appeal to many outside of her devoted cult. The record is allegedly divided into six “gardens” of songs, but the concept seems to have everything to do with maintaining Amos’s mystique and nothing to do with the songs themselves. “Sweet the Sting” and “Witness” belong to the “Rock Garden” and “Elixirs and Herbs” garden, respectively, but they share the same DNA: a creeping funk undercurrent, churchy organ flourishes, backing vocals from the London Community Gospel Choir, and lyrics concerning the union of the religious and the sexual. The “Elixirs and Herbs” closing track “Toast,” with its gentle acoustic guitar and halting piano arpeggios, sounds nothing like “Witness.”

Amos’s voice is as strong as ever. Her growls on the infidelity pot-boiler “Hoochie Woman” rival such past triumphs of rage as “Little Earthquakes’s” “Precious Things” and “The Waitress,” from 1994’s “Under the Pink.” She sounds giddy and girlish on “Ribbons Undone,” an ode to Natashya. Her lyrics pulsate with the joy of reshaping language to fit her needs. “Can somebody tell me now, who is this terrorist / Those girls that smile kindly then rip your life to pieces,” she sings on “The Power of Orange Knickers,” emphasizing that romantic and physical violence can be equally devastating.

But the music is suffering. Amos plays it too safe with her arrangements, featuring little more than lulling piano, tender drum beats and barely-there bass on most tracks. Almost every song maintains the same steady, plodding tempo. It’s pleasant but dull, more suited to waiting room background music than the emotional bloodlettings her earlier work seemed to conjure. At 19 tracks in 80 minutes, “The Beekeeper” feels like an interminable service in the Church of Tori.

Tori Amos will perform at the Hammerstein Ballroom April 8 at 6:30 p.m. (311 W. 34th Street, at Eighth Avenue, 212-777-1224).