In these passages is the account of the Apostles selecting seven men to serve and provide food for the followers who were widows. They selected men with ‘good reputation, full of the spirit and wisdom’ to do this task. One of them was Stephen, who the Bible says was ‘full of grace and power. He was performing great wonders and signs among the people.’
Stephen was not one of the Apostles, yet he was able to perform ‘signs and wonders.’ Evidently, the Apostles had the power to bestow miraculous powers on other disciples.
I believe that these powers ceased after the Apostles died. They are not evident today. Today we do not need signs and wonders to believe. The Bible is sufficient for our understanding and guidance.