Why are there so many Trinitarian heresies?

The words are given us in the scripture to awaken our worship rather than to add to our information. I agree that they are simple, that they are easy to read; only we make the most tremendous mistake if we suppose that because they are easy words we can necessarily understand them. The words of inspiration are true, and clear and distinct; and these words set out for our faith the blessed person of our Lord Jesus, Christ, God manifest in flesh. Therefore on such a theme we cannot, we should not, trust ourselves to use any words concerning our Lord Jesus Christ that do not exactly coincide with what the Spirit of God has already written. All the failures and errors of doctrine that bestrew the devious paths of Christendom since the days of the apostles are due simply to the efforts of men to define and limit what is indefinable and illimitable about the Lord Jesus, Christ. What human tongue is competent to tell His praises and His worth, and what mind could probe the mystery of His Person? Let us receive the words of Holy Scripture concerning Christ Jesus just as they are written, and hold them fast exactly as the Spirit of God has given them to guide our poor wandering minds into eternal truth, and our renewed hearts into reverent worship.

It is the height of folly for man with his finite mind to try to reason and speculate about that which is infinite. Every time he attempts to do so he is sure to fall into some error by introducing some human idea derived from purely human relationships into his reasonings about the uncreated, eternal, unchanging and unchangeable relationship subsisting in the essential Being of the eternal Triune God, which is far above and beyond human relationships and lies away outside the scope of human reasoning powers to speculate about.

This reasoning of the human mind about the Godhead has led to different errors by introducing certain elements that have to do with our human relations down here into their reasonings about the Godhead, but which evidently cannot be applied to that eternal, uncreated, unchanging and unchangeable relationship that subsists between the three persons of the Triune God.

This reasoning of the human mind about the Godhead has led to different errors by introducing certain elements that have to do with our human relations down here into their reasonings about the Godhead, but which evidently cannot be applied to that eternal, uncreated, unchanging and unchangeable relationship that subsists between the three persons of the Triune God.

Despite the many Scripture passages that clearly describe how the oneness of God includes three Persons‑the Father, the Son and the Holy Spirit‑the Trinity remains one of the most difficult concepts for Christians to understand or explain to other people. How three persons can be one God called the Trinity is a puzzle to natural reasoning. If you try to see God your creator in natural or creature-like terms, then you want to believe He is some kind of infinitely powerful person who is THE BOSS. If He is such a gigantic, all‑powerful person, then how in the world could He be three big persons or even three smaller persons at once?

Now we cannot understand that which is so far above us, the nature of God — that which is infinite; but it is necessary to see that scripture clearly speaks of the Father as God, and the Son as God, and the Holy Ghost as God; and yet, as the creed says, there are not three Gods, but one God. So it is necessary to see that the Lord Jesus was truly a man, born of the Virgin Mary; that He lived a man upon the earth, was then nailed to a cross of wood, and died — died to redeem His people. Being man, He could die; His being God as well as man gave infinite value to His death for the redemption of an innumerable multitude. Our Lord Himself said that no man knew the Son but the Father (Matt. 11:27), and therefore we cannot expect to understand the mystery of the union of God and man in one Person. Many who have attempted it have fallen into error; some have denied the Godhead and others the manhood of our Lord. It is our wisdom to believe every statement of scripture, though we cannot understand that which is infinite, nor the Person of our Lord, as He Himself said. We shall see, later on, to what evil the Arian heresy led in the church.

But, not only is it an unobjectionable term, and one which has been sanctioned by our greatest divines, as Owen, Goodwin, Bunyan, Gill, etc., but it expresses what could not be so well or so clearly conveyed by any other. Those who so strenuously object to it, may not, perhaps, be altogether aware either of the time of its introduction or of the reason why it was first introduced. It is, then, not only one of those concise and convenient expressions which divines in all ages have employed to communicate scriptural truth in a clear, definite form, but was first used for this very purpose by the ancient Fathers. The necessity for the use of clear and definite terms soon arose in the Christian church; for as errors and heresies sprang up at a very early period as so many tares sown by the enemy of souls among the wheat, men of God felt themselves compelled to meet the subtle wiles of the adversaries of truth by proofs drawn from the Word of God. But besides adducing exact scripture language, it was found necessary, as error assumed a bolder front, to adopt specific terms, in order to define the truth more clearly; for it was soon discovered that erroneous men sheltered their heresies under scripture phraseology, assigning to it all the while a meaning of their own distinct from its true and received, acceptation. When, then, Arius in the fourth century broached his doctrine of the Son’s being generated of the Father before time, but not from all eternity, and that, therefore, there was a period when the Son was not, the ancient Fathers made choice of the term “eternal generation,” to distinguish the proper and eternal filiation of Jesus from His generation in the sense of Arius, who admitted the generation of the Son, but not His eternal generation, and craftily used generation in the sense of making or forming, not begetting. He thus denied that the Son was co-equal, co-eternal and con-substantial of the same substance with the Father. To oppose, then, this fearful heresy, which was, in fact, a denial of the Deity of the Lord Jesus Christ, and degrading Him to a mere creature, the early Fathers employed the term “eternal generation” to express concisely what is stated more largely in the Nicene Creed, “Begotten of His Father before all worlds,” “begotten, not made, being of one substance with the Father”-”begotten before all worlds,” in opposition to the Arian doctrine of a “begetting which was not eternal;” “begotten, not made,” in opposition to the interpretation of begetting as a being made; and “of one substance with the Father” in opposition to the Arian heresy that He was not of the same, but only of similar substance.

Today in Christendom there is another widespread error that also is the result of introducing another element of human relations into the divine, uncreated, essential relationship that subsists in and between the persons of the Triune God. They say that the term son implies "graded relations and relative inferiority"; and therefore they reason the term "Son of God" can only apply to Him as Man born of the virgin and can have no application to His pre-incarnate relationship in the deity. This terrible error robs Him of His pre-incarnate relationship as Son well beloved of the Father which is the keystone of the whole New Testament.

With these words our author launches us into deep waters. It was during the fourth century that one Apollinarius, in opposing the Arians, who emphasized Christ's Manhood and denied His Deity, formed the theory that in Christ the Word (Greek, Logos) took the place of the rational element in man; or in other words that our Lord assumed only a human body, and that the Divine nature in Him took the place of the rational human soul or mind. By this he hoped to meet the Arian heretics on their own ground, and give a rational explanation of the otherwise inexplicable mystery of His Person.

The warning against Rationalism, in the things of God, was early unheeded in the history of the professing church. It is not without very serious reflection that we see how the early heresies in the church of God sadly affected the minds of God's people as to the Person of our adorable Lord. There were the Gnostics (Greek, gnosis, knowledge). They maintained that a Divine Person could not unite Himself with that which is human. They contended that our Lord's body was an appearance only, an apparition, and that He only seemed to live upon earth. It is thought that these doctrines were alluded to in John's first Epistle, where it is said that "every spirit that confesses Jesus Christ is come in the flesh is of God," and that the denial of this great truth is the spirit of Antichrist. Then there were the followers of Arius, who taught that the Son was not of the same substance as the Father. The church of God owes a great debt, to this day, to Athanasius, who boldly stood for the truth, involving him in bitter persecution, and going into exile again and again. There was a veritable crop of various theories concerning the Person of our adorable Lord in the early days of the professing Church, many of which have their counterpart in the Modernism and Higher Criticism of the present time.