"So water baptism only saves the believer in type . . . Peter is careful to inform his readers that he is not teaching baptismal regeneration, namely, that a person who submits to baptism is thereby regenerated, for he says, ‘not the putting away of the filth of the flesh.’ Baptism, Peter explains, does not wash away the filth of the flesh, either in a literal sense as a bath for the body, nor in a metaphorical sense as a cleansing for the soul.
Although I agree that salvation is possible without a baptism of water, I could not disagree with the above statements more.
First, it is you who added the statement “nor in a metaphorical sense as a cleansing for the soul.” Peter didn’t say this, nor does the verse in question imply it.
Let’s break the verse down. “. . . not as a removal of dirt from the body” We both agree that the function of baptism is not to remove the “filth of the flesh.” " . . . but as an appeal to God for a clear conscience." Here, Peter isn’t saying “the removal of dirt doesn’t save you; the appeal to God for a clear conscience saves you.” Rather, he is saying, “Baptism doesn’t wash dirt from your body; it appeals to God for a clear conscience.” Or, to put it another way, “Baptism doesn’t save you this way (washing dirt); rather, it saves you THIS way (appeal for a clear conscience) through THIS power (the resurrection).”
The earliest Christians clearly understood baptism in this way. For example, Barnabus wrote: “We indeed descend into the water full of sins and defilement. However, we come up, bearing fruit in our heart, having the fear and the trust in Jesus in our spirit.”
“The seal, then, is the water. They descend into the water dead, and the arise alive.”
The Shepherd of Hermas
“We who have approached God through Him have received, not carnal, but spiritual circumcision, which Enoch and those like him observed. And we have received it through baptism by God’s mercy, since we were sinners.”
Justin Martyr
None of us here denies that salvation is possible without baptism. But Christ established normative means of chanelling his grace, and in His great mercy provides it when those means are absent.
And (not to stray too far from the subject at hand ) as for your statement that “any interpretation which comes to the conclusion that baptism, or any other act, is necessary for salvation is a faulty interpretation,” you have Matthew 6:14-15, Matthew 18:23-35, Luke 14:26, all of Matthew 25, and Romans 8:17 to reckon with.