[UntoHim]

Well I took the context to be that Moses and Paul "were both well-versed in the language, the thinking, and the philosophy of their cultures".

I wouldn't presume to speak for Ravi Zacharias, but I think the general point is that Moses and Paul were not just "spiritual", and unengaged with the culture (including the language and philosophy) around them. I think this dynamic is clearly shown with Paul's interactions with the various cultures in the book of Acts, and even in the various epistles that went out to various churches with different cultures (Jewish, Greek, etc.)
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