On the other hand, we are explicitly told elsewhere that justification is by grace through faith, NOT by any human works (Ephesians 2:8-9). That is consistent with Acts 2:39, but not with the Oneness version of Acts 2:38.
What is wrong with the Oneness interpretation? Well, the problem is that they insert a form of works righteousness, salvation by baptism, into a verse that says so such thing.
If I say, "I took an aspirin for a headache," would any rational person understand me to mean that I took an aspirin to GIVE me a headache? Of course not! Rather, "for" there means "because of," not "in order to." And the reference to baptism for the remission of sins in Acts 2:38 is grammatically identical.
Therefore, Acts 2:38 proclaims baptism as a recognition of the justification that comes by faith ALONE, just as verse 39 tells us. It is ONLY the bad Oneness distortion of the verse that could be seen to indicate otherwise.