The central focus is on the life and teaching of the new body of believers (4:32-37), not on their approach to political concerns. Because the powers' demands for love and exclusive, however (as are the Lord's), their jealously is inevitably provoked. The strength within this new body is so real, compelling, and different, that the authorities respond with force in arms, arrest, plans to drag them before the council.
But then comes this little story of the angel of the Lord opening the prison doors, and of renewed preaching in the temple. This tiny little episode is barely a bump in the plot, for a few short hours later the apostles are dragged right back in again, to the same situation.
Or are they? Is the whole point just to give them a couple of extra hours of teaching? Surely it matters that this teaching occurred, for the apostles were specifically commanded to do so by the releasing angel; but it seems that the importance of this plot turn lands more on the ongoing nature of the church's mission than on the particular hours of teaching that morning. In the face of anything, the Lord's work goes on (this is seen in full effect in 28:31, where Paul, under house arrest, is said to preach "without hindrance.")
To return to the question, the apostles do not return to the same situation. Same place, same people, same exercise of authority, but not the same situation at all. In vv22-24, the council is utterly perplexed by their own failure to exert their authority. They are not converted, for they fail to recognize the Lord at work in the empty prison cells. They are not "defeated" exactly, for they retain their positions of power. They are entirely perplexed, and in their perplexity their positions of power are shown up as less than absolute, and their demands for loyalty are revealed as undeserving of a positive response. They are disarmed.
The situations at the council in 5:21 and 5:26 are very, very different indeed. As the powers are disarmed, the power of God at work in the church (and elsewhere) is able to show forth more clearly, and the missionary task of Christ's followers is able to continue unhindered; it cannot be arrested.
To further push the point home, this disarming is not even the main point of this passage or book. In the primary point, which is the message about Christ and its proclamation, the powers and their destiny are an incidental side-note. Even as a topic of concern, they are temporal at best. I believe this has profound implications for our political existence in a democratic society, but further reflection is for another day. Instead, here I can conclude only as this passage does in Acts 5:42. May it be so among us as well.
"And every day in the temple and at home they did not cease to teach and proclaim Jesus as the Messiah."
