This Eternity of God is argued in general, 1. by God’s Independence, which, a. as it posits God as Necessarily Existing, so also as abiding with eternal duration in His Existence. We set it forth as proven that God necessarily exists in § 21, page 592; hence it follows that God also exists as Eternal without beginning, end, or succession. For, if He should have a beginning, He had not existed necessarily before His beginning: if He should have an end, when that had arrived, He would no longer necessarily exist. And, what does not have a beginning and end is not able to have parts nor a succession of parts; for, where there are the successive parts of duration, there finite duration obtains, there then some part would be first, and another would be able to be last. b. An Independent Being also either always existed; or does not even now exist. For, if it were not at some point, whence began it to be? Not of itself: for what is not, is not more able to cause itself than it is able to be and not be at the same time. Neither was it able to be produced by another, because in this way Independence is taken away, nay, Deity itself. Similarly, if God now is, He also always will be; since the Consummately Perfect Being fails not from any intrinsic defect, neither is the Independent Being destroyed by any external force.
2. The Immutability of God proves the same, whereby He, being altogether free, not only of mutation, but also of mutability, is not able to have a beginning to His existence, since thus He would at some point pass from non-being into being; neither is He able to end, since what is now Deity, will no longer be entirely so then, but will be completely annihilated: but neither is succession in Existence able to be assigned to God, since mutation would obtain in God’s Duration, which does not differ from the enduring God Himself, and so God moment-by-moment will be changed into another, no less than we.
3. The Scripture expressly claims Eternity for God; in Genesis 21:33, He is called יְהוָ֖ה אֵ֥ל עוֹלָֽם׃, Jehovah, the everlasting God; in Isaiah 40:28,אֱלֹהֵ֙י עוֹלָ֤ם׀ יְהוָה֙, the everlasting God, Jehovah; in Romans 16:26, κατ᾽ ἐπιταγὴν τοῦ αἰωνίου Θεοῦ, according to the commandment of the everlasting God. But, that in this sense God is also called נֵ֣צַח יִשְׂרָאֵ֔ל, the Strength/Everlastingness of Israel, who לֹ֥א יְשַׁקֵּ֖ר, will not lie, 1 Samuel 15:29, our AUTHOR concludes, following JUNIUS and TREMELLIUS[1] and partly COCCEIUS in his Lexico, so that it might be the Eternity of Israel, or the eternal God of Israel; who might be abstractly called Eternity, since this Essential Attribute of God does not differ really from the Essence of God Himself. While others translate it, the Victory, Strength of Israel. Neither interpretation is foreign to the context here: BUDDEUS, Historia ecclesiastica Veteris Testamenti, period II, section III, § 5, tome 2, page 44b, “He calls God נֵ֣צַח יִשְׂרָאֵ֔ל, the Victory of Israel, that is, Him, to whom alone we ought ascribe our victories over enemies: although the notion of eternity is also able to come into consideration here, which most aptly agrees with the immutability of the divine decrees.” But the Most Illustrious SCHULTENS from an Arabism assigns to this word the notion of unmixed or sincere purity, and so he renders this passage: the Consummate Truth of Israel, that is, the pure Truth of Israel, God who is most pure Truth, does not make a lie: see SCHULTENS on Provers 21:28, pages 268b-271. Again, the Most Illustrius VRIEMOET, Thesibus Scripturarum CCCXIV, writes on this passage, “You might best explain נֵ֣צַח יִשְׂרָאֵ֔ל from the use of the Arabic נצח, concerning faithful care, with which God was embracing His people.” Indeed, he also observes in Thesibus Scripturarum CCCCLXXXVII that נצח among the Arabs and Chaldeans denotes to take charge with care and counsel.
[1] John Immanuel Tremellius (1510-1580) converted from Judaism to Christianity and quickly embraced the principles of the Reformation. He taught Hebrew at Strasburg (1541) and at Cambridge (succeeding Paul Fagius in 1549), and served as Professor of Old Testament at Heidelberg (1561).