A more perfect union and I were discussing this itty bitty word upthread. As best I can discern from your long post here in 194, you also believe that εἰς meant because of and not for.
Which is wrong.
See posts 109 and 110 for more details in εἰς.
Not quite. "For" can and does here mean "on the basis of" as one of its implementations in English. Doing his/her best the translator translates, the interpreter interprets, and the translator tries not to take on the task of interpreting. That is why I went back to the Greek and enunciated on what is permitted for this broad word "eis" from Wittman's "The Gospels: A Precise Translation" in its Glossary regarding the preposition εἰς, citing from The Greek Lexicon second revised version by F. Wilbur Gingrich and Frederick W. Danker, which devotes five columns to this word and its uses.
To rest your argument on the English is not a wise approach. To translate this as "so that" or "in order that" (which is what you want) is to choose a meaning in context that would not occur to the Greek-speaking brain of the first-century follower of the Jesus whose baptism of them only inducted them into discipleship. Baptism did not obtain salvation for them. Only belief in His work substituting for them did that. Actually, Peter was not converted even the night before Jesus was crucified, was he, even though he was baptized not only by John Baptiser, but by Jesus at he beginning of his training?
Now why would Peter even imagine that baptism of water would produce salvation as its effect on the spirit of the one baptized? And what if, as often seems to happen, the one baptized just walks back into his old patterns and never demonstrates conversion, but reversion. Were his sins really remitted? Does he have to be baptized again if he is to avoid the Lake of Fire? Oh, my, what a mess you have if your theory is of the Gospel. As well as losing your salvation. Etc.
You can bring up all the scholars you want, but they can never supersede the Holy Scripture, which explains itself. Remember, the primary target audience of the New Testament was the Greek-speaking Gentile, who never heard pf English. It is the context communicared in Greek of what this disciple has learned about the mind and culture of Christ that effects a correct interpretation of Peter's use of εἰς in this exclamation, not consorting to a centuries-later "scholar" who himself is prejudiced by his own viewpoint.
I'll go with the way Jesus used εἰς in Matthew 12:41 as fitting the doctrine of salvation by faith, not by works.