The light of truth needs to shine brighter with each passing day. The concept of progressive revelation is very important. This is because we are in darkness and do not fully comprehend the light. Cut off from the God's presence by our collective and individual sin humanity needed God to slowly pull back the shades of night.
Following the barrier that was imposed by man's first sin, God has been attempting to restore His image through a greater revelation of himself. First speaking through nature, then through His law, then through the prophets, He finally provided the ultimate revelation through His Son. This revelation was encapsulated through the written word and has been handed down to us through the ages.
Now Christians believe that the cannon is closed and in their ardent desire to preserve God's word they have limited the Holy Spirit. Galatians 3 tells us that the law was to be a tutor that leads us to Christ. The words of scripture testify of Christ, but they are not Christ. Jesus is a living person that breaths and speaks today.
We are too comfortable with the fact that we have hindsight and are not looking for insight. Does God only desire us to live by the letters written down by the ancients. Jesus commenting on what was correct behavior on the Sabbath day, explained that if we help an ox out of a ditch we should be even inclined to help a man on the Sabbath day.
God is speaking today. He wants us to respond to Him personally. The bible will never be contradicted by a Spirit led life, but with the Spirit comes further light. We cannot be content with the past. We need to live in the present. We need to listen to God's words for us today in such a time as this.