Q: Whose names have been changed in the Old Testament and New Testament?

A:  Abram -> Abraham, Sarai -> Sarah, Jacob -> Israel, Shadrach->Hananiah, Meshach->Mishael, Abednego->Azariah and > Cephas -> Peter

Changing of names was a common feature in the biblical periods, in order to show a change of nature within that person. I believe master's were able to change their slaves names. (Some scholars believe this is what happened with Paul, since we're left without biblical reason for his name change.)

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