This means they [Christians] have no moral and ethical allegiance to anything, including the OT and its laws that is logically prior to Jesus Christ.(p68)This means in practice that we must read our Bibles with the NT having the final say on every issue it addresses (p6) and giving it logical priority over the OT. There are numerous problems when we give the OT a logical priority. Wells illustrates:
What will happen if we start at Genesis and build our doctrine of the people of God from consecutive readings of the OT? Among other things, we will have a pretty thorough and extensive idea of who the people of God are, long before we come to the NT. The people of God is Israel, the physical descendants of Jacob and, before him, Abraham.What would then follow would be the inclusion of the Gentiles in Israel; a flattening out the two covenants so that they become two administrations of the same covenant; and finally an identification of the old covenant sign (circumcision) with the new (baptism). A similar problem is faced when Sabbath observance becomes a binding ordinance for Christians, despite the NT insistence to the contrary (see Romans 14:5).
...What would be the consequences of this reading?...We might easily assume that since there is one people of God, God would only have one covenant with them and one sign of the covenant, circumcision. When we arrived at the Major Prophets, if we were particularly perceptive, we might make some small adjustments. Of course the NT, when we came to it, would change our convictions on these matters, but we would have a predisposition to find as little change as possible. After all, we know there is one people, one covenant, and one covenant sign. (p9)
Despite efforts by Reformed theologians, the Decalogue cannot function as a compact summary of all moral law. The contrived efforts of the Westminster Divines to shoe-horn an implicit command for obedience to every human authority under the fifth commandment is an example of this (see Shorter Catechism q64 and 65)
No, the law that governs Christians is the 'law of Christ' i.e. the teachings, warnings and commands of Christ embodied in the New Testament writings (gospels and epistles). The law of Christ must have absolute priority in the church and even OT commands must not be read apart from it's authoritative glory. What of the OT? Wells recommends:
...the re-examination of the OT with the idea in mind of finding those things that are moral laws in the light of the NT and that are in keeping with the explicit demands of the Lord Jesus Christ in the NT. (p75)In the light of what's been said about Israel and the law, Wells defines what he means by the New Covenant:
The New Covenant is the bond between God and man, established by the sacrificial death of Jesus Christ, under which all who have been effectually called to God in all ages have been formed into the one body of Christ in NT times, in order to come under his law during this age and to remain under his authority forever. (p75,76)Next, what about not one jot or tittle passing from Moses in Matthew 5:17-20?