You are well aware that it is against our law for a Jew to associate with or visit a Gentile. But God has shown me that I should not call anyone impure or unclean.
On the one hand, Peter here is depicted as saying that it is against the Jewish Law – that is, unbiblical, contrary to Scripture, in violation of what conservatives tend to call the Word of God – for a Jew to associate with a Gentile.
We can discuss whether this statement is strictly speaking true – but if it isn’t, that serves as a warning that even Peter, and/or the author of Acts, could be persuaded that something is unbiblical when it in fact was not.
The contrast is stark, and today’s conservative Christians would expel Peter from their churches for daring to say such a thing, were he to say it today.
The irony is that there are many Christians who emphasize that they are “Biblical” as though that were a good thing, as though by saying that they were providing proof positive of their Christian identity. Yet according to this passage, being “Biblical” is the hurdle that Peter has to get over in order to get on board with what God was doing in his time.