Well since you're disappearing, there doesn't seem to be much point in replying in depth.
Two quick points. Firstly, Christ is everywhere in the OT. 'These are [the Scriptures] that testify of Me' (John 5:39). Christ's covenantal role is seen as early as Gen 3:15.

Secondly, Baptists are not by any means required to judge infallibly on anyone's salvation. We baptize as the Apostles did, on a person's profession of faith. Water baptism is not the seal of the New Covenant, Spirit baptism is (Eph 1:13-14). Water baptism brings no one into any covenant. Simon Magus was baptized in water, but his heart was unchanged. Therefore Peter told him, "You have neither part nor portion of this matter, for your heart is not right in the sight of God" (Acts 9:21).

Baptism is the outward sign of something that has already happened inwardly (Acts 10:47). If nothing has happened inwardly then baptism is irrelevant.

Have a nice break!
Every blessing,
Steve

Itinerant Preacher & Bible Teacher in Merrie England.
1689er.
Blogging at
http://marprelate.wordpress.com