19 Grk “And after.” Because of the length and complexity of the Greek sentence, καί (kai) has not been translated here. Instead a new sentence is begun in the translation at the beginning of v. 7.
20 Grk “making them”; the referents (Peter and John) have been specified in the translation for clarity.
21 By what name. The issue of the “name” comes up again here. This question, meaning “by whose authority,” surfaces an old dispute (see Luke 20:1–8). Who speaks for God about the ancient faith?

In other versions

And when they had set them in the midst, they inquired, “By what power or by what name did you do this?”

They had Peter and John brought before them and began to question them: “By what power or what name did you do this?”

After they had Peter and John stand before them, they began to question them: “By what power or in what name have you done this?”

They brought in the two disciples and demanded, “By what power, or in whose name, have you done this?”

And they made them stand in their midst and began to ask, “By what power or by what name did you do this?”

And when they had set them in the midst, they asked, By what power, or by what name, have ye done this?

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