This information page gives an overview of Kenneth Smith, links to many resources, and posts scans of his classic run of TCJ columns. The scans contain his most essential writing, but there is a Tumblr blog and a Gaim library that provide quotes from longer pieces. Here are some choice fragments.
via Integral Life:
Some type of reincarnation doctrine is found in virtually every mystical religious tradition the world over. Even Christianity accepted it until around the fourth century CE, when, for largely political reasons, it was made anathema. Many Christian mystics today now accept the idea. As the Christian theologian John Hick pointed out in his important work Death and Eternal Life, the consensus of the world religions, including Christianity, is that some sort of reincarnation occurs.
Of course, the fact that many people believe something does not rank it true.