One of the greatest challenges for us in reading the Bible is how we, as Christians, are supposed understand the Old Testament. While we all agree that it is the inspired word of God, each Christian traditions weighs the force of its precepts differently. There are those who would say they take it literally, and use Jesus' words from today's Gospel as proof that Jesus wanted to keep the law. After all, he told the leper to "Go, show yourself to the priest and offer for your cleansing
what Moses prescribed." I would dare say that even the most fundamentalists, really pick and choose: eating pork, or wearing clothes of two different threads. There are others who feel free to simply pick and choose individually what parts of the Bible they will interpret how.
From our Catholic perspective we recognize that we must take the scriptures as a whole and all must be examined through the lens of the Gospel. For us the Holy Spirit lives, and our understanding of God's word continues to deepen. The word does not change but our understanding of it does. That is why Jesus gave the church a shape, a structure, to guide that ever deepening understanding of the truth that is contained in every part of scripture, a truth that in some cases is immediately apparent, and in some cases requires an understanding of language, culture, and context that not every person possesses. We believe that every part of scripture has some truth to teach us, and the tool God has given us to help unlock that truth is called the magisterium.