圣 (shèng, 'holy/saint') is the standard Chinese prefix for 'Saint' in Western names — compare
圣彼得堡 (St. Petersburg),
圣保罗 (São Paulo / St. Paul).
詹姆斯 (Zhānmǔsī) is the standard transliteration of James, also used for individual figures like James
詹姆斯·
邦德 (James Bond) or LeBron James
勒布朗·
詹姆斯.