Baptism, of course, has been habitually associated with the word “regeneration.” What is being reappropriated [in the Book of Common Prayer 1979], however, goes far beyond previous arguments over the meaning of that word in PECUSA’s history. As associated with the Paschal Mystery, Baptism is more forcefully than ever before exhibited as a sacrament and not an event, i.e., it is not the substitution or recognition of a nature other an ordinary human nature, but rather the effective declaration of human nature properly constituted. In more traditional language, Baptism is an outward and visible sign wherein what God has done and is doing in-and-for humanity is declared, and persons incorporated into that powerful relationship are essential to it, i.e., individuals are incorporated into a society – the Church, the Body of Christ – which is not apart from historical human society as such, but specifically intended by its life and mission to be revelatory of human society’s true constitution. As connected, then, with the centrality of the Paschal Mystery, Baptism is disclosed as potentially the most radical and political act into which human beings are capable of entering.
William E. Peterson, “The Tensions of Anglican Identity in PECUSA: An Interpretive Essay” Historical Magazine of the Protestant Episcopal Church, Vol. 47 no. 4. (Dec. 1978) p.446