The obtaining an union with Christ, is the one life and immortality brought to light by the gospel; but this immortality unavoidably requires, and necessarily implies the perpetual duration of the soul’s natural life. For nothing but an ever-enduring creature, is capable of enjoying an everlasting gift.
Therefore the gospel, tho’ never once expressly asserting, yet continually demonstrates the natural immortality of the soul.
And this is the whole truth, with regard to the Mosaic history and types; they hide it, in the same manner as the gospel hides it, that is, not at all; and they fully prove it in the same manner as the gospel proves it, by doctrines which necessarily require, and absolutely imply it, in the first conception of them.
For the history of the creation and the fall of man, contains an express covenant of a redemption, promised to Adam and his fallen posterity, in which a seed of the woman should do away the evil which the serpent had brought into the human nature, that is, should restore the first, lost, heavenly life to mankind.
But this covenant, and the immediate benefit of it, could neither be wanted nor received, but by immortal creatures, that believed themselves to have an immortality, which had lost that glory and perfection which belonged to it at the first. Nor could such immortal creatures have any power of entering into this covenant any other way, than by an implicit faith in God. For it was a covenant of redemption, or return of their first glory, without the least intimation of the time, or age, when, or the means, or manner how it was to be brought to pass. Therefore such a covenant, and such a faith, in the very first conception of them, without the least reasoning or deduction, absolutely imply, and necessarily require a full belief of a future state.
And how could God better keep up a full sense of it, or more fix it in the hearts of men, than by placing and fixing all their faith and comfort, in a redemption certainly to come upon all the world, which yet might not come, till half the world was dead?
Or how could mankind possibly give into this faith, had they had the least doubt of the certainty of a life to come? For their faith in such an expected redemption, could not be either more or less, than their faith in a future state.
Therefore God’s requiring this faith of them, was in the highest degree his requiring them to believe the ever-enduring life of their souls. Consequently, in the first revelation of God to man, life and immortality, as it means an ever-enduring state of the soul, was as fully, and in the same degree brought to light, as in the revelation of the gospel.
In the gospel it is proved, because an immortality of a heavenly life is made known, purchased and given by Christ, which necessarily implies an immortal nature in man, or he could not partake of it.
In the first revelation, it is equally proved, because a redemption to come, that was to be obtained by an implicit faith, without any knowledge of the time when it was to appear, whether before or after many generations of men were dead and gone, necessarily implies a full belief of a state belonging to man, that is beyond time, and the death of the body.