About Baptism for the Dead and the Argument that the "Mormon" Temples Are Not the Same Gospel that Paul Taught, etc.

Baptism. 

Jesus invited us all to be baptized. 

We know that we cannot be saved without baptism. We know that God is merciful and just and would not condemn anyone just because they were born in the wrong place and the wrong time. 

Baptism by proxy for our dead is God's answer to that apparent injustice and is His invitation to us to learn one more way to exercise faith in Jesus Christ.

In a similar way, every doctrine of the temple simply extends the doctrines of the Gospel to the dead -- the very same Gospel as taught by Paul, Peter, Jude, John, Moroni, Mormon, Alma, Nephi, Isaiah, Moses, Enoch, Noah, and all the prophets, the very same Gospel as taught be Jesus Himself.

Otherwise, the dead would be taught a different doctrine, a different gospel, and, since we must all pass through death, we would all face a different gospel and a dilemma that would destroy us.

The doctrines of the temple ordinances are neither more nor less than bringing faith in Jesus Christ, repentance, baptism by immersion, and the gift of the Holy Ghost through Jesus Christ's own authority -- bringing the Gospel of Jesus Christ to our dead, because without their salvation, we are as dead ourselves.