Authorizing Marriage?

The opponents of legal recognition for same-sex marriage frequently appeal to a "Judeo-Christian" tradition. But does it make any sense to speak of that tradition as a single teaching on marriage? Are there elements in Jewish and Christian traditions that actually authorize religious and civil recognition of same-sex couples? And are contemporary heterosexual marriages well supported by those traditions? As evidenced by the ten provocative essays assembled and edited by Mark D. Jordan, the answe