I. It is a matter of the greatest moment, that we learn distinctly to consider the covenant of grace, either as it is in its substance or essence, as they call it, or as it is in diverse ways proposed by God, with respect to circumstantials, under different economies. If we view the substance of the covenant, it is but only one, nor is it possible it should be otherwise. There is no other way worthy of God, in which salvation can be bestowed on sinners, but that discovered in the Gospel. Whence the apostle, Gal. 1:7, has beautifully said, “which is not another.” And that testament which was consecrated by the blood of Christ, he calls “everlasting,” Heb. 13:20, because it was settled from eternity, published immediately upon the fall of the first man, constantly handed down by the ancients, more fully explained by Christ himself and his apostles, and is to continue throughout all ages, and, in virtue of which, believers shall inherit eternal happiness. But if we attend to the circumstances of the covenant, it was dispensed “at sundry times and in divers manners,” under various economies for the manifestation of the manifold wisdom of God. In considering this, we are first to discourse on those general things which appertain to the substance of the covenant, and have continued in every age; and then explain the different economies or dispensations, and the new accessions made to each; which we will, first, do in a general and concise manner, in this and the following chapter; then gradually descend to the more special considerations.
II. We therefore maintain, agreeable to the sacred writings, that to all the Elect, living in any period of time: 1st, One and the same eternal life was promised. 2dly, That Jesus Christ was held forth as the one and the same author and bestower of salvation. 3dly, That they could not become partakers of it any other way, but by a true and lively faith in him. If we demonstrate these three things, none can any longer doubt, but that the covenant of grace must be, as to its substance, only one from the beginning. For, if the salvation be the same, and the author of it the same, the manner of communion with him the same, it is certain, the covenant itself cannot be more than one.
II. The Scriptures so plainly declare, that eternal life was promised to the Elect from the beginning, that if is astonishing any Christians could venture to deny it; who, indeed, are much blinder than the Jews themselves; of whom our Lord testifies, John 5:39. “Ye do search the Scriptures, for in them ye think ye have eternal life:” and that they were neither rash nor erroneous in thinking that the promises of eternal life, and the manner of enjoying them, were contained in the Scriptures they had, we prove by the most cogent arguments. 1st, Because, not only the Lord Jesus does not charge them, in this respect, with the least error, but makes use of that as a reason to recommend to them the search of the Scriptures. But it is very inconsistent with the great sincerity of the Lord Jesus, and the divine dignity of the Scriptures, to recommend them by arguments not genuine, or to recommend their value and usefulness from Jewish forgeries. Nay, had the Jews falsely persuaded themselves, that the promises of eternal life were contained in the Old Testament records, our Lord ought not, by any concession, to have cherished that mistake, which would have hindered them from acknowledging the excellence of his doctrine, and consequently the divinity of his person; but rather to have exclaimed against them: “In vain do you search the Scriptures, in hopes of finding eternal life in them; attend rather to me and my doctrine, who am the first who came into the world as a preacher of eternal life.” But every one may see how inconsistent this was from the design of the Lord Jesus. 2ndly, To this we add, that Paul’s hope was founded on the Law and the Prophets, as well as the expectation of the Jews, Acts 24:14, 15, “Believing all things, which are written in the Law and the Prophets; and have hope towards God, which they themselves also allow, that there shall be a resurrection of the dead, both of the just and unjust.” He testifies, that the Jews expected a resurrection of the dead; he professes the same belief and hope with them; and that he did not do so out of a vain presumption, but from a faith resting on the Law and the Prophets, which they also, in their manner, carefully read, and from which they had derived the same expectation with him. 3dly, The Jews were so far from judging amiss in this respect, that, on the contrary, the Lord Jesus reproved the Sadducees, as ignorant of the Scriptures, because from them they had not learned life eternal and the resurrection, Matt. 22:29.
IV. But let us argue from the very books of the Old Testament: and first, after the example of our Lord, who, Matt. 22:31, 32, speaks to this purpose: “But, as touching the resurrection of the dead, have ye not read that which was spoken unto you by God, saying, I am the God of Abraham, and the God of Isaac, and the God of Jacob; God is not the God of the dead, but of the living.” This inference appeared so evident to the multitude, that they were astonished at his doctrine, and the Sadducees were put to silence, ver. 33, 34. And, indeed, if the words of Moses, quoted by Christ, be accurately weighed, the evidence of this argument will easily appear to the attentive reader.
V. For, 1st, That expression, to be God to any, in its full import, includes life eternal, For, when God becomes the sinner’s God, he then becomes to him what he is to himself. But, what is he to himself? Doubtless, the fountain of eternal and complete blessedness. When God, out of his grace, gives himself to man, he gives him all things; for himself is all things. Such a man finds in God “a shield” against every evil, and an “exceeding great reward,” Gen. 15:1. And what can he desire more in order to his perfect happiness? Accordingly, the apostle joins these two, Heb. 11:16, God to be the God of any one, and to have prepared for them a city. And seeing the “gifts” of God’s grace, especially when he gives himself, “are without repentance”, Rom. 11:29; hereby also the eternity of this happiness is established.
…XVII. But lest they should cavil, that we borrow our arguments only from the New Testament (though none can better instruct us in the contents of the Old Testament than Christ and his apostles), we shall consider some passages of the Old Testament, and free them from the misconstructions of our adversaries. And, first, we have that swanlike song of Jacob, Gen. 49:18. לישועתך קויתי יהוה “I wait for thy salvation, O Lord.” The aged Prophet was now at the point of death; and, being full of the Spirit of God, he, in the midst of his prophecies, in which he foretels what was to befall his children and latest posterity, breaks out into these words; which were not spoken without the Spirit of God, so as, with Smalcius, to be referred to a vain persuasion, nor possibly to be wrested to any other but this spiritual and eternal salvation.
XVIII. Here, again, let a certain Jew put the followers of Socinus, if possible, to the blush: in opposition to whom we produce this paraphrase of the Jerusalem Targumist. “Our father Jacob said, My soul does not expect the redemption of Gideon, the son of Joaz, that being only momentary; nor the redemption of Samson, because a transient redemption; but the redemption thou hast mentioned in thy word, or by thy word, which is to come to thy people, the children of Israel; my soul, I say, expects this thy redemption.” Is not this a very clear testimony of the most certain persuasion and the fullest assurance of their salvation?
…XXXIII. When the same apostle affirms that our “salvation at the first began to be spoken by the Lord,” Heb. 2:3, it is clear he speaks of the Gospel completed, and of the Messiah, the author of salvation, already exhibited; which Gospel the Lord first published, with respect to the apostles, evangelists, and the other ordinary preachers that followed them. For otherwise who can deny that Zacharias, the father of John the Baptist, and Mary the mother of our Lord, and the angels who proclaimed his nativity, and the aged Simeon, and John the Baptist, were preachers of salvation before the Lord? Of the Fathers the apostle himself affirms, that they were ευαγγελισμενοι, gospelized, or that “the Gospel was preached unto them as well as unto us,” Heb. 4:2.
XXXIV. When it is written, Heb. 9:8. “That the way unto the holiest of all was not yet made manifest, while as the first tabernacle was yet standing;” the apostle indeed intimates, that the manner of obtaining salvation was, in some measure hid, in comparison of the brighter lustre of the Gospel. For then, doubtless, the way to life was clouded with much pomp of ceremonies and figures; which being now dispelled, we behold with open face, and ardently desire, heavenly and spiritual things. But from this it no ways follows, that those under the Old Testament had no knowledge of salvation; any more than it can be concluded, we know nothing of our glorious state, because John says, “It doth not yet appear what we shall be,” John 3:2. We may almost, in the same manner, answer the other objections advanced by our adversaries. But it is no part of our design to examine each in particular.
XXXV. Now let us proceed to the second thing, which we undertook to prove; that in Christ, and in virtue of his suretiship, the fathers of the Old Testament also obtained salvation even as we. Which Peter declares almost in so many words, Acts 15:11: “But we believe that, through the grace of the Lord Jesus Christ, we shall be saved even as they.” Where the pronoun they is to be referred to the fathers, on whose neck an insupportable yoke of ceremonies was put, as appears both from the grammatical consideration of the gender, from the connexion and the force of the apostles argument. For, since κᾀκεῖνοι is masculine and τα ἔθνα, the Gentiles, mentioned ver. 7, is neuter, it is not so properly referred to the Gentiles as to the fathers. And we are not here, without necessity, to have recourse to an enallage of gender. And then, too, what method of commenting is it, to imagine so wide an hyperbaton or transposition, and to bring from verse 7 a noun, to which, after the interposition of so many other things, a pronoun shall at length answer in eleventh verse, and which yet does not answer; because, in the words immediately preceding, you may find a noun, with which the pronoun in question may be very well joined? In fine, it will either be nonsense, or, very insipid, if the words be so construed. For, what manner of reasoning is it, if we suppose the apostle to have said: “The yoke of ceremonies ought not to be put on the necks of the Gentiles, because, we Jews and apostles believe, that we shall be saved in the same manner as they, by the alone grace of the Lord Jesus Christ?” For besides this, it was improper to propose the Gentiles, to the Jews and apostles, as a pattern of salvation, because it appears, that the contrary should be done; and we could only conclude from that position, that the apostles and Jews were not bound to circumcision, and the other ceremonies, any more than the Gentiles. But that was not the thing in dispute. But according to our interpretation, the apostle argues in the strongest manner: “You ought not to put the yoke of ceremonies on the necks of the disciples, who are converted from among the Gentiles, because the fathers themselves, who were under that yoke, really felt the uneasiness of it, but did not find salvation in it, and yet they were saved, not in consequence of these ceremonies, but by the grace of our Lord Jesus Christ. Neither are we, nor any of the human race, to take any other way to attain salvation. They therefore are under a mistake, who tell the disciples, if you will be saved, you must be circumcised, and keep the law of Moses.” To sum up the whole, then, in short, the apostle here declares three things. 1st, That the fathers were saved. 2dly, By the very same covenant that we are. 3dly, Through the grace of our Lord Jesus Christ: intimating likewise by all this reasoning, that there can possibly be but ONE way of salvation.
XXXVI. This is likewise confirmed by that famous passage, Heb. 13:8, “Jesus Christ the same yesterday, and to-day and for ever.” In the foregoing verse the apostle admonished them to keep fresh in their memory “the word,” which their guides had spoken unto them, whose faith they should follow. Now, he gives this for the reason of that admonition, because “Jesus Christ is the same yesterday, and to-day, and for ever;” constantly preached by all the teachers of the truth, believed on by all, and to be believed on by those that come after, if they will imitate the faith of their predecessors. The same doctrine therefore is always to be retained, because Christ, who was always both proposed, and believed, as the author of salvation, changeth not. But the particles, yesterday, to-day, and for ever, denote all the differences of times. Nor does yesterday here signify something of a late date, as we usually say, yesterday or lately; but all the time past: as the phrase to-day denotes the time of grace under the New Testament. For, this is compared to some one present day, as chap. 3:13. “While it is called to-day:” and chap. 4:7. “Again, he limiteth a certain day, saying in David, To-day,” &c.; of which 2 Cor. 6:2, “Behold! now is the accepted time, behold! now is the day of salvation.” As, therefore, Christ is to-day, under the New Testament, acknowledged the alone author of salvation, and will be acknowledged as such for ever; so, in like manner, yesterday, under the Old Testament, which day is now past, he was the same, and as such was declared and acknowledged.
XXXVII. Let us also add what we have in Heb. 9:15, “And for this cause he is the mediator of the New Testament, that, by means of death, for the redemption of the transgressions that were under the first testament, they which are called might receive the promise of eternal inheritance.” Where we have an open declaration, that the death of Jesus Christ was effectual for the redemption of transgressions committed under the Old Testament. For thus the apostle proceeds. He supposes that the fathers of the Old Testament were saved, notwithstanding their sins; which Socinus, with his followers, dare not deny. He says further, that the blood of bullocks and of goats, and consequently of all sacrifices whatever, could not really, and before the tribunal of God, expiate sin, and purify the conscience. Yet since, as he declares, without shedding of blood there can be no remission, verse 22, he concludes, it was necessary that the death of Christ should indeed be undergone, in order not only to the establishment of the New Testament, but by virtue of which the redemption of former sins might also be obtained. This is the genuine meaning of the sacred writer.
XXXVIII. And, indeed, Grotius shamefully shuffles, when, to favour the Socinians, he thus writes on this place: “His death intervened for this end, that men might be delivered from those sins, which generally prevailed, before Christ, among those called God’s people.” Is it really so? Would thus “the redemption of the transgressions that were under the first testament,” denote such an action of Christ, whereby succeeding ages would abstain from the like sins, as were formerly committed? God forbid we should ever pervert Scripture thus. Redemption is כפד an expiation of sin, upon paying a ransom. Christ paid this for all the sins of his elect, at whatever time they lived. And upon the credit of that payment, to be made at the appointed time, believers, even under the Old Testament, obtained redemption.
XXXIX. Moreover, since it is evident that Old Testament saints were saved, it must likewise be evident that they were saved through Christ. For our Saviour himself says, John 14:6: “No man cometh unto the Father but by me.” And Peter, Acts 4:12: “Neither is there salvation in any other; for there is none other name under heaven given among men, whereby we must be saved.” Nothing can be plainer than these words, which seem to be written as with a sun-beam. Yet the itch of contradiction has found something to say, but that something is less than nothing.
XL. Our adversaries except, that these passages should be understood of those who live under the New Testament, and therefore that both Christ and Peter speak in the present, and not in the past time; of us, and not of the Old Testament saints; of the times when Christ was exhibited, and not of the Old Testament times. We answer: 1st, As both texts are expressed in universal terms, they are not to be limited without cause and necessity, as there is none in this case. For if salvation could be obtained formerly without Christ, equally as now through Christ, what need had we of Christ’s coming? Or, what so very great matter do we obtain in Christ? 2dly, There are very solid reasons, why they neither ought nor can be thus restricted. Because they who were “without Christ, were strangers from the covenants of promise, having no hope, and without God in the world.” Eph. 2:12. 3dly, The quibbling about the verbs being of the present time is idle, because verbs of that time or tense may equally refer to all times. And whatever expression had been used, whether denoting the future or past time, there might always be room left for such cavils. Besides, no reason can be assigned, why the past time should be excluded any more than the future, if that verb of the present tense is thus to be racked. If this is not false reasoning against the Supreme Being, and a childish abuse of one’s genius and parts, what can be called so?
…XLIII. The apostle writes nothing in opposition to this truth, when he says, Gal. 3:23. “But before faith came, we were kept under the law.” For it is far from the apostle’s intention to deny, that faith in Christ prevailed before his coming in the flesh, because, in the same chapter, he had highly commended the faith of Abraham, and proposed it as a pattern to us all, ver. 6, 7, 9. But by faith we here understand either the object of faith, the doctrine of the Gospel, as chap. 1:23, and the Lord Jesus himself, believed on in the world, 1 Tim. 3:16, or, the faith of the redemption already actually wrought out, as contradistinguished from the hope of the Old Testament saints, who, with earnest longing, as it were, expected the coming of the Lord, “waiting for the consolation of Israel,” Luke 2:25. And thus we have now shown, that the Old Testament saints had the same promises of eternal life with us, to be obtained by the same Christ, and the same faith in him, and consequently also had the same covenant of grace with us.
Herman Witsius, The Economy of the Covenants between God and Man: Comprehending a Complete Body of Divinity, trans. William Crookshank, vol. 1 (London: T. Tegg & Son, 1837), 259–73.