It's no secret that it's hard to be good, but who knew the effort could be so funny? Clark's second novel is a pumped-up joyride across the rocky terrain of modern ethics and faith. Joel King, the Baptist minister of a well-heeled congregation in Roanoke, Va., canoodles unwisely with 17-year-old Christy Darden, a girl who gives hilarious new meaning to the term ''bad seed.'' King serves time in the lowly city jail, where ''each day was the same dull progression of idle chatter, crackpot philosophy, food complaints, hopeless escape schemes and jokes about the dandruff on the guards' brown shirts.'' Upon his release, he's slapped with divorce papers and a $5 million lawsuit from Christy. Fortunately, King isn't friendless: Edmund, a devoted parishioner and sociopath, lures him into an irresistible insurance-fraud scheme. Clark's prose is dense, but in the manner of an enormous gourmet hot fudge sundae: sweet and wicked.