The Gunsmith #364: The Vicar of St. James by J. R. Roberts
...FOR I HAVE SINNED
Deputy Marshal Clint Adams is surprised to hear from Father Joseph, his old friend who was once an armed and dangerous man known as Joe Holloway. Now remade into the first Vicar of St. James, Father Joseph has invited Clint to the first wedding he’s presiding over. But when the wedding takes a deadly turn, Clint stays in town to investigate two murders—and winds up uncovering some dangerous secrets that are sure to put him in harm’s way… OVER 15 MILLION GUNSMITH BOOKS IN PRINT!