Few thoughts for consideration:
Baptism wasnt a new thing in the OT, the jews were baptising long before jesus, or john arrived on the scene.
Baptism by water was done because they were once baptised into the name of moses. And the whole splitting of the red sea was gods way of baptising the entire nation into the name of their 'saviour' moses. The entire nation, went throught the waters.
And so i guess, it became tradition to baptise the next generations of jews in the name of moses as well, in water. (but god wasnt going to split it every time
)
In any event. When john started to baptise, along came the pharisees. They figured it was appropriate to baptise themselves. John was not too happy about that. The isrealites of old were baptised into moses's name because moses was the frontman for their salvation. But they relied on moses's clout with god, and didnt think they needed to have a change in heart! So he said they should REPENT!
Now the gentiles have jesus as their frontman. Their saviour. And we too had to be baptised into his name. We were baptised in his name on the cross, baptised into his death, so that when he arose from the dead (or when he emerged from the 'red sea') we too would come along right with him, on our way to the promised land.
I dont think that there is anything wrong with being baptised in water, its an outward act of what happened inwardly already.
Heneni
