Although Kline wants to restrict the works principle to Israel’s inheritance of Canaan and associated temporal blessings, he considers these as typological of the blessings of the covenant of grace. These blessings, received by us through grace, are founded on Christ’s meritorious obedience to the covenant of works as the second Adam. Let us suppose for a moment that this was so. If this argument is correct, the archetypal blessings of salvation in Christ would be received by grace through faith, as Kline acknowledges, but Israel would receive the typological blessings, such as Canaan, by meritorious law-keeping according to the works principle. These, Kline has stated, are two alternative, antithetical ways of inheritance. But a type corresponds to the antitype. If the one is a type of the other, we conclude either that the blessings of the covenant of grace are received by law-keeping on the part of the recipients – in which covenant were to be received by grace, which undermines Kline’s argument. The only other possibilities are either that law and grace work together, in distinct ways, or that the typical relationship is untenable; in both cases the argument is undermined.
Robert Letham, “Not a Covenant of Works in Disguise”, Mid-America Journal of Theology, vol. 24, 2013.