The risen Jesus is the stone that you rejected but whom God has made the cornerstone of his building. Today’s First reading from the Acts of the Apostles is a continuation of the unfolding of events that followed the healing of a crippled man by the apostles Peter and John (cf. Acts 3:1ff). The healing of the man had brought some excitement at that part of the Temple where they were and a large gathering was fast forming. Peter, sensing the awe with which the people were now looking at them, took the opportunity to preach to them about the risen Jesus. But their preaching about the resurrection of Jesus of Nazareth – especially Peter’s bold claim that that their leaders had instigated Jesus’ death – did not amuse the religious leaders. Determined to put a stop to any “open” talk about the resurrection, they promptly came to where Peter and John were preaching and whisked them away. The following day, the two apostles were brought before the Sanhedrin and questioned about their activities on the previous day. Peter’s address before the Sanhedrin which is the content of our reading today is an answer to the question posed to them by the court: “By what power, and by whose name have you men done this?”
From their question, it is clear that even the authorities recognized that something incredible had happened. They also recognized that Peter and John were mere mortals ( you men) and as such were in no position to work the miracle of the healing using their own power. Peter sensed a golden opportunity and he did not hold back. Filled with the Holy Spirit, he reiterated the point he had made the day before: “It is in the name of Jesus the Nazorean whom you had crucified that we are able to work these mighty signs before your very eyes.” But Peter did not stop there. He went ahead to tell the authorities to their face that although they had rejected Jesus, God did raise him up and made his name the highest in the entire universe; that despite the authorities rejecting Jesus to the point of instigating for his death, God did raise him up as a vindication of his righteousness. And most importantly, God was going to it was through this very Jesus that God was going to make a new creation.
Peter’s address before the Sanhedrin was not given as an accusation of the authorities or the elders of the people. Peter was only intent on using the opportunity to witness to the great event of the resurrection and to the transformation that it was bringing about. For Jesus’ resurrection was not only about Jesus as an individual or about his small band of followers. The resurrection was an event that had ramification for the entire created universe. God was bringing the old order to newness in Jesus of Nazareth (salvation). Peter’s address was thus an extension of an olive branch to the authorities and the elders of the people. It was not yet too late for them to repent from their sins and embrace the new way that Jesus was carving out for creation. Though guilty of trumping up charges against Jesus which led to his execution, their guilt and past actions were part of the old order that died in the death of Jesus. 
The two apostles were given a stern warning to desist from speaking to anyone about the risen Jesus of Nazareth. However, the fear that had characterized their actions prior to Jesus’ execution was now replaced by courage that was out of the ordinary. Peter would go on to give a few more addresses as he continued to proclaim the risen Jesus. He became the symbol of the transformation that the Jesus’ resurrection effects in his followers. 
-  Ndugu Jeff -