In the first chapter of the book of Acts we read these words,“But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth.”
We find here a powerful statement by Jesus describing the expected behavior of the Christian life — “ye shall be witnesses unto me.” But what does it mean to be a witness?
Imagine that you witnessed an auto accident and have been called by the court to come and testify on behalf of one of the involved parties. You are sworn in and are now obligated by your word, to tell the truth. But the truth of what? The truth of what you know to be true, based on what you saw and experienced.
You aren’t telling the story of what the guy across the street saw, you are solely giving witness to what you know to be true based on what happened to you.
This is also what it means to be a witness for Christ. To share your faith, you don't have to have a doctorate in theology; you are simply telling someone else what you know to be true, based on what happened to you.
If you are a Christian, you experienced the life changing power of Christ when you heard the Gospel, repented of your sins and trusted in Christ. You were radically changed. You know it to be true because it has changed everything about who you are.
Now you are to take that knowledge, both of how it happened (the hearing of the Gospel with repentance and faith) and exactly what happened (you became a new creation) and you are to tell others about it. But how?
Look back to the beginning of the verse, “But ye shall receive power.” Here we see the promise of the Holy Spirit that will empower us to be witnesses. When we become a Christian, the Holy Spirit comes and fills our life. He becomes an active part of who we are and we receive him in his fullness. This is great news for us as Christians. We aren’t expected to do this on our own but we have been given all that we need to do it by the power of the Holy Spirit.
As Christians we are to be sharing the Gospel; it’s non-negotiable. Christ’s examples of Jerusalem, Judea, Samaria and the farthest places on the globe as the arena of witnessing leaves no place and no people outside the bounds of the gospel.
The gospel of Christ is for all people, in all places and as Christians, we have been tasked with taking it there. But we don’t have to do it alone. Praise God for the Holy Spirit that empowers us to be the faithful witnesses Christ has called us to be.