Expositor's Bible Commentary Commentary Acts 4:7

"And when they had set them in the midst, they inquired, By what power, or in what name, have ye done this?" — Acts 4:7 (ASV)

It was before such an assembly, which probably arranged itself in a semicircular fashion, that Peter and John were brought. The man who had been healed was also there (cf. v.14), though Luke does not say whether he had also been imprisoned or had been called in as a witness. The apostles were called on to account for their actions, and they used the occasion for an aggressive evangelistic witness.