Quoting from the Catholic Encyclopedia:
"In Scripture there is as yet no single term by which the Three Divine Persons are denoted together. The word trias (of which the Latin trinitas is a translation) is first found in Theophilus of Antioch about A.D. 180. He speaks of 'the Trinity of God [the Father], His Word and His Wisdom' ("Ad. Autol." II, 15). The term may , of course, have been in use before his time. Afterwards it appears in its Latin form of trinitas in Tertullian ("De pud." c. Xxi). In the next century the word is in general use."
Words have been added to the writings of the Messianic Scriptures to try to reinforce the belief in the trinity, which actually has its roots in paganism.
Look at your English translation of 1 John 5:6-8. The New King James Version says, "This is He who came by water and blood -- Jesus Christ; not only by water, but by water and blood. And it is the Spirit who bears witness, because the Spirit is truth, for there are three that bear WITNESS IN HEAVEN: THE FATHER, THE WORD, AND THE HOLY SPIRIT; AND THESE THREE ARE ONE. AND THERE ARE THREE THAT BEAR WITNESS ON EARTH: the Spirit, the water, and the blood; and these three agree as one."
The Interlinear Bible (direct translations from the Hebrew and Greek) tells us that verses 7 and 8 of the above text contain twenty-five words that
have been added by the translators. They have been typed in caps and bold print.
The translation from the original texts (and using the Messiah's true Name, Y'hoshua), reads as follows: "This is the coming through water and blood, Y'hoshua HaMoshiach; not by the water only, but by the water and the blood. And the Spirit is the witnessing, for the Spirit is the truth. And there are three that bear: the Spirit, the water, and the blood; and the three are one."
You can see that the added words twisted the meaning considerably.
As further explanation on the statement about pagan sources of the trinity, the following information was taken from The Dallas Morning News, Saturday, May 10, 1997, page 2G, entitled, Room for One More: "While Hindus believe in one god, they also believe that he has taken many forms, first as the trinity of Brahma, Vishnu and Shiva and then as other forms over the millennia, Dr. Shah said. Dattatreya, who is especially popular with devotees in the Indian states of Karnataka and Maharashtra, is portrayed with three heads and six arms, symbolizing the unification of the trinity of gods when he was born."
We need to study diligently in order to KNOW what the Word says and not rely on what someone tells us it says. Eternal life is too important to leave in the hands of someone else.