If you read the whole of Acts 4 its about Peter and John preaching to the people about Jesus’s resurrection through the power of the Holy Spirit. Peter and John where locked up and accused of false testimony. That evening when they where locked up they had convinced a number of people – 5000 in all.
The following day they came before the Council. The people of the council were too scared to do anything because they would have a riot on their hands. They had healed a cripple man with the power of the Holy Spirit. Because that is what they where telling the people and they believed it. Resurrection power which is available to all believers through Jesus. The Council released Peter and John because they healed a cripple man of forty years and everybody saw that.
The Council warned them that they should stop telling this story. Peter and John reacted, and said they won’t take instruction from them. Their instruction comes from God alone. When they where released they got together with other believers and prayed. And so the Good News of Jesus was spread.
Take the time to read the whole off Acts 4 its an amazing account.