If you'll be in L.A. that weekend, you'll get a rare chance to step inside some of the most architecturally significant and just plain interesting religious buildings in the western U.S. Included is the huge Angelus Temple (designed by Brook Hawkins, 1923), across from Echo Park Lake, the original home of Aimee Semple McPherson's Foursquare Gospel church. (McPherson's story as a religious leader and media personality is gripping and improbable, pure Hollywood noir.) Other places of worship on the tour include the campus of the new-age Self-Realization Fellowship in the former turn-of-the-century Mount Washington Hotel; the modernist Chapel of the Jesus Ethic (1966) in Glendale; and the Philosophical Research Society in Los Feliz, designed by architect Robert Stacy Judd in "Mayan Revival" style in 1936. (Mayan Revival also influenced Frank Lloyd Wright's L.A. work of the '30s.)
Personally, I'd add another stop to the tour, for both architectural merit and religious variety: Rudolf Schindler's Bethlehem Baptist Church (1944), at 4900 Compton Avenue, in South Central L.A. The church is Schindler's last standing public work (or at least it was still standing as of the last Google Maps survey). The building's stucco "stripes" and cross-tower with skylight are still striking, even in its current state of graffiti-tagged, liquor-store-adjacent decay; and if not for its high-crime surroundings and decades-long history of neglect, it would probably be considered one of the L.A. modernist's greatest (and most conservation-worthy) works. Check out flickr users mayerwarsh and marieray for recent pics of the church, along with the remarkable (and depressing) Google Maps streetview (zip code is 90011).