The aim of your sermon is to help God’s people understand the main purpose of the old Mosaic covenant, and how it relates to the covenant made with Abraham and how it is fulfilled in Christ. Having done so, you will explain how we are meant to handle and interpret the old covenant law. Emphasize the fact that there are not two peoples of God (Israel and the church), but one people, namely those who have faith in Jesus Christ.
15 To give a human example, brothers: even with a man-made covenant, no one annuls it or adds to it once it has been ratified.