Francis Cheynell (1608-1665), a member of the Westminster Assembly, was nicknamed “the hammer of the Socinians,” since he exerted much effort into defending the doctrine of the Holy Trinity against Socinians and Unitarians. Whilst the Papists (and especially the Jesuits) often argued in defense of the Trinity not only from Scripture, but appealed particularly to tradition, Cheynell regarded the latter as a very unstable foundation for such a crucial doctrine. Here, in his work The Divine Trinunity of the Father, Son, and Holy Spirit, chapter 3, he argues that the doctrine of the Trinity has been sufficiently revealed in Scripture. Notably, he points to the church fathers as precedents regarding the sufficiency of Scripture in proving the doctrine of the Trinity:
God hath sufficiently and graciously revealed himself in his holy word for our edification and salvation.
This incomprensible God, who is of himself and for himself, cannot be made known to his creatures but by himselfe: Men and Angels cannot know him any further then he is pleased to reveale himself unto them.
The word of God is pure and perfect, it doth fully discover Gods mind and our duty. The Scriptures direct us in all points of faith, in all parts of worship, and in all passages of our life and conversation; there is the whole body of Religion, and the only right way to salvation sufficiently and graciously revealed unto us by God himself; for God is the Author, Object, End of true Religion, and is the only happinesse and salvation of his chosen People, and therefore God alone can direct us how to serve and enjoy his own blessed self, in an acceptable and comfortable way, for his glory and our own everlasting satisfaction.
The Jesuites tell us that the Scriptures are but a partial Rule, and that we must be beholding to some unwritten word or tradition for the proofe of some points, which are necessary to be known and believed for our everlasting salvation. Some instance in the Doctrine of the Trinity, others in the Worship of the Holy Ghost. The Papists do generally acknowledge that it is necessary for the attainment of salvation to believe the number of the Persons of the Trinity, and their consubstantiality, because no man can be saved who doth not believe in the Father, Son and Holy Ghost, in all three as in the only true God, one and the self-same God blessed for ever; but some of them deny that this mystery is sufficiently revealed in the written word, and therefore I shall make it my businesse to confute them and all that adhere unto them in the following Treatise. The saving knowledge of God in Christ is revealed by the Spirit speaking in the Scriptures of truth; nay Father, Son and Holy Ghost do all join in revealing to us the saving mystery of faith and godlinesse, that by the grace of Christ, the love of God, and Communion of the Holy Ghost, we may have a glorious fellowship with all three as one God, the only true God, whom to know is life eternal, John 17. 3. we are taught by the father to come to Christ for salvation, John 6. 45. we are taught by the son, John 1. 18. Heb. 1. 2. we are taught by the Spirit, Heb. 3. 7. Rev. 2. 29. and 1 John 5. 6. the Spirit doth beare witnesse after an especial manner to this saving truth: it is the spirit that beareth witnesse, because the Spirit is truth: yet all three (and therefore the whole Trinity, the Father, the Son and the Holy Spirit,) do join in bearing record, and their record is written, for it stands upon Record in the Gospel, and their Record is a saving Record, and there can be no other Record produced to prove that Christ is our Saviour, 1 John 5. 7, 11, 12, 13, 20. John 20. 31. if we study the Scriptures, believe, apply them, worship and act according to them, we shall be saved by our faith in the written Trinity; in Father, Son and Holy Ghost, without the help of any unwritten tradition whatsoever; for the holy Scriptures are able to furnish the Man of God unto Perfection, and make the simple wise unto salvation, 2 Tim. 3. 15, 16, 17. Cyrill in his Book of the Trinity and Person of Christ, put forth not long since by Wegeline, saith that he would not speak or think any thing of God, but what is written in his Word. Clemens Alexandrinus saith that we ought to make good every point in question by the Word of God, because that is the surest, nay that’s the only Demonstration; he speaks of Theological Demonstration, nothing can be embraced with a divine faith, but that which is delivered to us upon Divine Testimony; and we are to seek for the Testimony of God, nowhere but in the written Word of God, and therefore Basil disputes after this manner, Whatsoever is not in the written Word of God is not of faith, and whatsoever is not of faith is sin, and therefore it is a sin to obtrude any Doctrine upon the conscience as an Article of faith, which is not written in the Word of God. Putean is bold to say, that if Basil his meaning was according to his words, he was a Hugonot, that is as we use to say, a Puritane.
When I read what the Papists write on this Argument, I stand amazed at their blasphemies, and am unwilling to stain my paper with the repetition of them; they who have read Canus, Hosius, Costerus, Eckius, Gautierus, Charronaeus, Stapleton, and the rest of that rabble, will not wonder that the Socinians call the Doctrine of 3. Persons and one God into question, when the Papists who were baptized in the name of the Trinity & professe that they believe the equality of three distinct Subsistences in the same divine Essence, do yet notwithstanding in their writings grant as much as the Socinians need prove, namely that the Doctrine of the distinction and equality of Persons in the same Divine Essence cannot be proved but by unwritten Traditions, by the testimony of the Church of Rome, &c. and yet diverse Papists undertake to defend the doctrine of the Trinity against the Socinians, though they know that the Socinians do not at all value traditions or the testimony of the Church of Rome; and therefore though divers Papists write against the Socinians, yet they do promote Socinianisme by their vaine doctrine of unwritten traditions. Stapleton is not ashamed to deny that it can be proved out of Scripture that the Holy Ghost is God, or that he is to be worshipped.
But Salmeron deserves commendation in this point; The Scriptures saith he, are therefore said to be written by divine inspiration, because they instruct us in divine mysteries, concerning the Unity of God, and Trinity of Persons. Photius in his Bibliotheca shews, that Ephraeni did not dispute of the consubstantial Trinity out of the Testimonies of Fathers, but out of the Holy Scriptures; Justin Martyr, Athanasius, Basil, Irenaeus, Cyrill, Cyprian, Tertullian, Epiphanius, Theodoret, and many other of the Fathers did assert the doctrine of the Trinity, and some of them did confute the Valentinians, Eunomians, Sabellians, Photinians, Arians, Macedonians, Samosatenians, &c. out of the Holy Scriptures. The Nicene Synod did urge Scripture for the maintenance of the truth, which they declared in the Confession of their Faith; and the Synod which met at Constantinople did the like, as is most evident to such as have perused those learned and ancient Records. Athanasius confounded the Arians by cleare Testimonies of Scripture, and in his Book of the Decrees of the Nicene Synod, he saith that the true disciples of Christ, do clearly understand the doctrine of the Holy Trinity preached by divine Scripture. I shall not trouble or amuse the Reader by quotations out of Cyrill, Ambrose, Hilary, Augustine, Nyssen, Nazianzen, or any of those Worthies but now mentioned, whole labours have been ever famous in the Church of God; yet I must not omit one pregnant proofe out of Augustine, who appealed from the Nicene and Ariminensian Synods, and challenged Maximinus to dispute with him about the great point of consubstantiality out of the Scriptures. Bellarmine himself is forced to confesse that Augustine had good reason to do so, because that point is cleare by Scripture; but then we must likewise consider what Augustine saith upon this Argument, that the thing (or sense of any word) may be in Scripture though the word it self be not to be found there, though the words Trinity Trin-unity, Consubstantial, are not found in Scripture, yet that which is signified by those words may be clearly proved by the holy Scriptures. These three are one; I and my Father are one; Behold a Trinity Trin-unity, Consubstantiality, and all quickly proved.
That Rule is of great concernment and very pertinent to the point in hand, which Augustine delivers in his third Book and third Chapter against Maximinus the Arian. Out of those things which we read in Scripture we may collect some things which we do not read, and so both understand and believe the thing which is delivered in other words in Scripture, then those which we are now forced to use, that we may confirme the Orthodox Christians and refute the gain-sayers. But I am weary of this task, and therefore call upon my Reader to join with me in searching the Scriptures that we may find out the truth; for reason cannot demonstrate or comprehend these mysteries of faith; and the Rule is, Rationum fulcro dissoluto humana concidit authoritas. [Own translation, roughly: Authority falls when based on the unstable footing of human reason.]