For it must necessarily follow that either all that is required for our salvation is not in Christ or, if all is in him, then those who have Christ by faith have his salvation entirely.

Therefore, to say that Christ is not enough but that something else is needed as well is a most enormous blasphemy against God– for it then would follow that Jesus Christ is only half a Savior. And therefore we justly say with Saint Paul that we are justified “by faith alone” or “by faith apart from works.”

However, we do not mean, properly speaking, that it is faith itself that justifies us– for faith is only the instrument by which we embrace Christ, our righteousness.

But Jesus Christ is our righteousness in making available to us all his merits and all the holy works he has done for us and in our place. And faith is the instrument that keeps us in communion with him and with all his benefits.