But... "he that believeth not shall be damned." It doesn't say "He that is baptized not shall be damned..." The key component necessary for salvation here is belief, not baptism. He that believeth will of course be baptized, but it is the belief in what Jesus Christ has done that saves us.
No one ever answered my question about this verse. How does batism save us? Well, the answer is right there in the verse:
1 Peter 3:21 (New International Version)
New International Version (NIV) Copyright © 1973, 1978, 1984
"21 and this water symbolizes baptism that now saves you also—not the removal of dirt from the body but the pledge of a good conscience toward God.
It saves you by the resurrection of Jesus Christ..."
The context is again key:
24 Wherefore the law was our schoolmaster to bring us unto Christ,
that we might be justified by faith. (Justified by faith, not by baptism!)
25 But after that faith is come, we are no longer under a schoolmaster.
26 For ye are all the children of God
by faith in Christ Jesus.
27 For as many of you as have been baptized into Christ have put on Christ.
28 There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for
ye are all one in Christ Jesus. 29 And if ye be Christ's, then are ye Abraham's seed, and heirs
according to the promise.