The doctrine of the covenant of redemption. Wherein is laid the foundation of all…

5 The Decree of God is a firm, stable, Immutable Purpose of his. A very Heathen could say, Nulla est Litura in De. cretis Sapientum. The Medes and Persians, under a proud opinion of their infallible Wisdom, set a Stamp of Immutability upon all their Laws. But this is peculiar and proper to the Purposes of God. Gods Wisdom is like himself, Infinite: he can never be wiser than he was, then when he established his Decree. He did it in Counsel, and his after thoughts cannot mend his former. It was his Will that things should be so, and he hath but one Will, which is not to be altered, Job 23.13. Nor can he ever want for Power to put that in Execution, which he hath purposed; for he can do every manner of thing. The Records of Eternity shall stand unshaken; what he hath said shall certainly come to pass, Prov. 19.21. Psal. 102.27.

6. The Son of God, who was thus constituted Redeemer in the Decree, is a Person in the God-head, infinitely free and uncompellable. Though the Doctrine of a Trinity of Persons in the Unity of the Divine Essence, be a Mystery beyond the capacity of our short Understandings to fathom; yet in as much as these are ⟨p. 17⟩exhibited to us under the notion of three Persons, each one having a distinct Subsistence, (though all have but one and the same Essence) we must therefore allow to each of them all that is Essential to the God-head: and thus we are to conceive of each of them to have a Divine Will; though it be one and the same in all. The Son of God, being God, is in this respect Coequal with the Father; for this reason he challenged this Equality as his due, Phil. 2.6. and God calls him his Fellow,