(1970) Elizabeth Peters, The Dead Sea Cipher (Dodd Mead)
Elizabeth Peters was the nom de plume of Barbara Mertz, the best-selling author of dozens of novels frequently set in the world of Near Eastern archaeology. (You can visit a site with biographic and bibliographic information here, maintained by Mertz's family company.) Mertz/Peters, who held a PhD in Egyptology, is perhaps most famous for her "Amelia Peabody" mysteries, set in the colonialist world of Egyptian archaeology in the Victorian era; two other series, set in the present day, featured strong women academic protagonists (Jacqueline Kirby and Vicky Bliss). (Here is the Guardian's appreciate obituary on the occasion of Mertz' death in 2013.) The Dead Sea Cipher, which also features a woman lead (rare in the Gospel Thrillers genre), was written before Mertz started in on any of these series.
This novel is the earliest to posit what would become a leitmotif of the Gospel Thrillers genre: the intimation that the discoveries of the "Dead Sea Scrolls" in the 1940s merely scratched the surface, and that other, perhaps more thrilling (and therefore dangerous) scrolls lay still concealed in the caves outside Jerusalem. With a touch of humor, characteristic of the "cozy" mystery genre Mertz embraced, Dead Sea Cipher also explores the growing interest in Jesus' Jewish origins and the fraught intersection of U.S., biblical, and Israeli identities.
Heroes: Dinah van der Lyn, opera singer, daughter of a Christian minister, granddaughter of a rabbi; while on a Holy Land tour she is caught up in a murder and race to uncover Dead Sea Scrolls relating to the life of Jesus (discovered by an alcoholic archaeologist); she also meets (and falls in love with) a gruff U.S. archaeologist (Jeff Smith)
Villains: A motley cast of local and international characters, some representing European powers, some religious groups, all out to claim or destroy the new scrolls; Cartwright, a suave mercenary and murderer, is a particularly dangerous foe
Gospels: In addition to early, Aramaic versions of the canonical gospels, the dead archaeologist had found a Life of Jesus and Life of Mary, which are destroyed by religious conspirators before their contents are revealed
Reviews: As an early Peters book, The Dead Sea Cipher didn't receive much attention in the press (the small squib in a group review below—including the novel Shaft!—is one of few national notices it received). As this Goodreads page shows, fans of Peters' later works have discovered the novel, but often complain that it does not rise to the level of her more mature works.