Genesis, chapter 2 verse 24, says a man "shall cleave unto his wife, and they shall be one flesh." But how liberally to define cleave? That was the very special Bible query the Rev. Stacy Spencer and his wife Rhonda took up last month with 252 married people at their New Direction Christian Church in Memphis, Tenn. And the Spencers' answer was ... encouraging. Does frequent sex have a place in marriage?