Acts 4:8-10, 13

Then Peter, filled with the Holy Spirit, said to them: “Rulers and elders of the people! If we are being called to account today for an act of kindness shown to a man who was lame and are being asked how he was healed, then know this, you and all the people of Israel: It is by the name of Jesus Christ of Nazareth, whom you crucified but whom God raised from the dead, that this man stands before you healed.

When they saw the courage of Peter and John and realized that they were unschooled, ordinary men, they were astonished and they took note that these men had been with Jesus.