“At baptism we make a covenant with our Heavenly Father that we are willing to come into His kingdom and keep His commandments from that time forward, even though we still live in the world. We are reminded from the Book of Mormon that our baptism is a covenant to ‘stand as witnesses of God [and His kingdom] at all times and in all things, and in all places that ye may be in, even until death, that ye may be redeemed of God, and be numbered with those of the first resurrection, that ye may have eternal life’ (Mosiah 18:9; emphasis added)” (Hales, “Covenant of Baptism,” 7).
What do the “gates of hell” symbolize? (11:40) “The gates of hell, then, does not refer to the devil at all; though his snares and wiles might lead men sooner or later to their death, delivering them ‘to the destruction of the flesh,’ his power ends there. The gates of hell are—the ‘holding back’ of those who are in the spirit world from attaining the object of their desire” (Nibley, Mormonism and Early Christianity, 108).
“Baptism for the dead, then, was the key to the gates of hell which no church claimed to possess until the nineteenth century, the gates remaining inexorably closed against those very dead of whose salvation the early Christians had been so morally certain” (Nibley, Mormonism and Early Christianity, 106).