It's not how long you've been born again that will make you an effective witness. It's not necessarily the tremendous insight you have into God's Word that will make you an effective witness. You can start with what you know now; and what you know now is what Jesus of Nazareth has done in your life.
Never get the idea that your testimony is no good because you weren't on drugs or because you hadn't made a horrible mess of your life before you met Jesus. I've heard people stand up and say, "I don't have a very good testimony. I've known Jesus all my life."
That's a tremendous testimony! There are people who want to hear it. So you can start now with what Jesus has done in your life. But don't stop there. You also need to get into God's Word. You need to know the Word that supports what Jesus did in your life. People are looking for evidence. They want evidence, and you can give it to them by the Word of God and by your own testimony. That's what a witness is: one who provides evidence.
As we see in Matthew 24, Jesus said that in the day and time in which you and I live Satan's agents - Satan's vessels - would be going about deceiving many. If they are willing to go and represent Satan, then we ought to be willing to go and represent Jesus!
The more of us who go out and win others to Jesus, the smaller Satan's kingdom becomes and the quicker his population decreases. When we become willing to take the Gospel to them, then that enables them to be delivered from the power of darkness and translated into the Kingdom of God's dear Son. The more active Christians become in witnessing, the faster we will see Satan's kingdom begin to diminish. But first we must be willing to go.
Excerpt permission granted by Jerry Savelle Ministries International