I had someone tell me last week that they didn't feel they could share their faith with others because they were a "baby Christian" and they didn't know alot about what the Bible said. I explained to them that their "story" was all they needed to know to begin to tell others. We can always share with others how God's love, grace and forgiveness has changed our lives. Even when you are a baby Christian, there is much to tell others so don't allow satan to tell you otherwise.
1 Corinthians 1:17 For Christ did not send me to baptize, but to preach the gospel, not in cleverness of speech, so that the cross of Christ would not be made void.
2 Corinthians 3:12 Therefore having such a hope, we use great boldness in our speech
My Bible's Commentary:
Some speakers use impressive words, but they are weak on content. Paul stressed solid content and practical help for his listeners. You don't need to be a great speaker with a large vocabulary to share the gospel effectively. The persuasive power is in the story, not the storyteller.