This world cannot argue with your own testimony. Even if you do not have all of the apologetic defenses lined up in your mind or the Hebrew and Greek words memorized, if you call yourself a child of God then at one time you were spiritually blind and now you see. That is it. Rest in that. Rejoice in that. Live in that. Know the One who gave you site. Sit at His feet and drink of His Truth.
In a world that questions, dwell in the only answer that satisfies the deepest longings: Jesus.