Five years after same-sex marriage became legal in Massachusetts, the local Episcopal bishop yesterday gave permission for priests in Eastern Massachusetts to officiate at same-sex weddings. The decision by Bishop M. Thomas Shaw III was immediately welcomed by advocates of gay rights in the Episcopal Church, who have chafed at local rules that allowed priests to bless same-sex couples, but not sign the documents that would solemnize their marriages. The decision is likely to exacerbate tensions in the Episcopal Church and the global denomination to which it belongs, the Anglican Communion, which has faced significant division in the wake of...