Those verses pertained to the law of the Old Covenant that Israel was under. It was only given to Israel, the Jews. Today we as Christians are under a new covenant and are not bound to the old. (Old testament / new testament). The law was a shadow of things to come, a preparation if you will. We don't follow them because they were not made for us or given to us and are not part of the covenant that we are now under. It is the same faith but a new set of rules.