1. The punitive justice of God is an essential attribute of his nature. This attribute renders the punishment of sin necessary, and is the foun- dation of the need of a vicarious atonement, in order to the pardon of sin- ners. This doctrine the apostle assumes as a first principle, and makes the basis of his whole exposition of the doctrine of justification, v. 18.
2. That sin is a proper object of punishment, and that, under the right- eous government of God, it shall be punished, are moral axioms, which have ' a self-evidencing light,' whenever proposed to the moral sense of men, vs. 18, 32.
3. God has never left himself without a witness among his rational creatures. Both in reference to his own nature and to the rule of duty, he has, in his works and in the human heart, given sufiicient light to render the impiety and immorality of men inexcusable, vs. 19, 20, 32.
4. Natural religion is not a sufficient guide to salvation. What indi- vidual or what nation has it ever led to right views of God or of his law"? The experience of the whole world, under all the variety of cir- cumstances in which men have existed, proves its insufficiency, and con- sequently the necessity of a special divine revelation, vs. 21 — 23.
5. The heathen, who have only the revelation of God in his works and in their own hearts, aided by the obscure traditionary knowledge which