What's the big deal about a new covenant?

In the context of the New Covenant there will be forgiveness and a Divine forgetfulness that will lose track of all our sins. But that forgiveness and forgetfulness are not so that God’s people may continue in their sin and rebellion. They are in order that the Old Covenant may be set aside and the New Covenant of the Spirit might be entered into. In that New Covenant, God’s people will be enabled to live for him as they could not when the covenant was external to them and not written on their hearts. — Called to be Holy, page 81

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Yes! But we must always remember that it is only by the power of the indwelling Holy Spirit. It is not outward performance. It is a transformed heart which results in holy living. That's why I have taken to calling it heart holiness. Otherwise we concentrate on works—a dead end it ever there was one!
</idle musing>