Through the illumination of the Holy Spirit, a person experiences rebirth. This is the most personal form of Gods revelation. Without the Spirit,we cannot understand spiritual things...but the Holy Spirit makes us alive in Christ. He gives us a new nature. He gives us a new capacity to see God in nature and history and to read the Bible with new understanding. A non-Christian will attend a Bible study, but nothing makes sense. Then suddenly something clicks and it becomes clear. The Holy Spirit has revealed to him in a personal way that Jesus Christ is God and that Jesus Christ is the Savior. He can now see what he couldn't see before. That person has been born again through the work of the Holy Spirit.