Brad Mehldau has been documenting his jazz piano mastery in trio and solo settings since the mid-’90s. But he also uses the studio to access other aesthetic realms, as he has before on 2002’s Largo (which featured flickers of hip-hop) and on 2014’s Mehliana: Taming the Dragon, with Mark Guiliana on drums and electronics. Guiliana resurfaces in a big way on Finding Gabriel, but as one component in a larger sonic canvas inspired by various biblical verses. Alongside the piano, Mehldau uses OB-6 synthesizer, Therevox, Moog Little Phatty (for rich bass tones), and other tools for a lush, modern sound, flecked with broken-beat elements or calmer rock-oriented grooves. A celebratory hip-hop chant of “hey hey hey” breaks out on “St. Mark Is Howling in the City of Night,” and it returns during the title track, which, like “O Ephraim” and “Born to Trouble,” features Mehldau alone playing all parts, including drums. There are also horns or strings on some tracks, beautifully orchestrated, at times with a dense, almost Bartókian dissonance (not to mention hellish soloing from trumpeter Ambrose Akinmusire and tenor saxophonist Joel Frahm). But most notably there are voices—those of Becca Stevens, Gabriel Kahane, Kurt Elling, and also Mehldau himself, weaving in and out to create a kind of spooky grandeur heard in classical works like Stravinsky’s Symphony of Psalms or Fauré’s Requiem. Unlike those pieces, both of which used Latin text, Mehldau’s vocal parts are all wordless—though he does recite verses from the Book of Daniel on “Finding Gabriel” and speak pointedly about the political climate on “The Prophet Is a Fool.” In all, it’s one of Mehldau’s most ambitious and unexpected efforts to date, full of power, mystery, and lament.