Witnessing at your own risk

This Sunday's reading from Acts 5:27-32 presents a powerful witness to the Gospel,

When they had brought them, they had them stand before the council. The high priest questioned them, saying, ‘We gave you strict orders not to teach in this name, yet here you have filled Jerusalem with your teaching and you are determined to bring this man’s blood on us.’ But Peter and the apostles answered, ‘We must obey God rather than any human authority. The  God of our ancestors raised up Jesus, whom you had killed by hanging him on a tree. God exalted him at his right hand as Leader and Saviour, so that he might give repentance to Israel and forgiveness of sins. And we are witnesses to these things, and so is the Holy Spirit whom God has given to those who obey him.’ 

If Jesus had not been physically seen and touched after he had risen, would these men risk their lives for a lie? 

If these men had not been filled with the Holy Spirit, would they have the had the courage to testify?

That may be all the witness someone needs to come to the conclusion that the Gospel is true.