The Watch Tower Society has spilled a lot of ink 'proving' to Jehovah's Witnesses that Jesus is, in no way, shape or form, God. As a result, some Witnesses make statements such as "God is not Jesus". But this is not a rebuttal of the Trinity. As Christians, we agree; God is not Jesus. But Jesus is God.
The rejection of Jesus as God stems back to the 3rd and 4th centuries and the Arian heresy. A read through of the assertions of this controversy will likely inform the reader as to where the Watch Tower Society (through the teachings and deductions of Charles Russell) get their ideas.
A proof text used by Jehovah's Witnesses to affirm their view that Jesus Christ, Son of God, is a created being (Michael the Archangel), is Colossians 1:15
" He is the image of the invisible God, the firstborn of all creation;"They emphasis the use of the term "firstborn" and conclude that this can and does mean that Jesus was created, the firstborn of Jehovah's creation.
Of course, with any honest exegesis, taking the context into account is essential. So,
"16 because by means of him all [other] things were created in the heavens and upon the earth, the things visible and the things invisible, no matter whether they are thrones or lordships or governments or authorities. All [other] things have been created through him and for him. 17Also, he is before all [other] things and by means of him all [other] things were made to exist, 18 and he is the head of the body, the congregation. He is the beginning, the firstborn from the dead, that he might become the one who is first in all things; 19 because [God] saw good for all fullness to dwell in him, 20and through him to reconcile again to himself all [other] things by making peace through the blood [he shed] on the torture stake, no matter whether they are the things upon the earth or the things in the heavens."For those unfamiliar with the [square brackets] here used in the text of the Watch Tower Society published New World Translation, these indicate words that have been inserted into the original language of the text (in this case Greek) by the committee who translated the NWT. As a side note, the Watch Tower Society has refused to name the Hebrew and Greek scholars who made up the NWT translation committee. Other translations such as the NIV and ESV take great care to name the translators used. This is done so that readers of their translation can evaluate whether these ones were qualified to accurately translate from the original languages into English. However, some have speculated as to the identity of the committee.*
In the above cited text from the NWT you will notice 5 instances of [square brackets] each containing the word [other]. Simply put, the anonymous NWT translation committee decided that the original Greek text need the word [other] added 5 times to these verses in order for English readers of the Bible to understand what God actually meant. (Readers wishing to verify whether the NWT accurately delivers the meaning from the original text should use a Greek Interlinear.)
When the above text is read without the inserted words, it takes on a completely different meaning; we see that Jesus created all things in heaven and on earth and he has authority over all things. If Jesus created all things, that means he existed prior to creation. If through and by Jesus all things were created, he himself cannot be a creating thing/being. I'll emphasis that; if Jesus is created, he must be part of creation. There is no room for that belief in the above text. And that's why the unnamed NWT translation committee saw fit to add their own meaning to God's inspired word.
Going back to Colossians 1:15, what is the reader to make of Jesus being described as "the firstborn of all creation"?
The Bible Knowledge Commentary has this to say;
How can Jesus be Michael the Archangel? How can Jesus be a created thing when he receives worship in heaven (Heb 1:6)? How can Jesus be a created thing, lower than God, when Thomas called Jesus "my Lord and my God" (John 20:28)?He is the Firstborn over all Creation. Though it is grammatically possible to translate this as “Firstborn in Creation,” the context makes this impossible for five reasons: (1) The whole point of the passage (and the book) is to show Christ’s superiority over all things. (2) Other statements about Christ in this passage (such as Creator of all [1:16], upholder of Creation [v. 17], etc.) clearly indicate His priority and superiority over Creation. (3) The “Firstborn” cannot be part of Creation if He created “all things.” One cannot create himself. (Jehovah’s Witnesses wrongly add the word “other” six times in this passage in their New World Translation. Thus they suggest that Christ created all other things after He was created! But the word “other” is not in the Gr.) (4) The “Firstborn” received worship of all the angels (Heb. 1:6), but creatures should not be worshiped (Ex. 20:4-5). (5) The Greek word for “Firstborn” is prōtotokos. If Christ were the “first-created,” the Greek word would have been prōtoktisis.“Firstborn” denotes two things of Christ: He preceded the whole Creation, and He is Sovereign over all Creation. In the Old Testament a firstborn child had not only priority of birth but also the dignity and superiority that went with it (cf. Ex. 13:2-15; Deut. 21:17). When Jesus declared Himself “the First” (ho prōtos; Rev. 1:17), He used a word that means “absolutely first.” “Firstborn” also implies sovereignty. The description “firstborn” was not a fairly common Old Testament designation of the Messiah-God. “I will also appoint Him My Firstborn, the most exalted of the kings of the earth” (Ps. 89:27). While this regal psalm refers to David, it also designates the Messiah, as seen in Revelation 1:5, where Christ is called “the Firstborn from the dead (cf. Col. 1:18) and the Ruler of the kings of the earth.” So “Firstborn” implies both Christ’s priority to all Creation (in time) and His sovereignty over all Creation (in rank).
These are questions any honest Jehovah's Witness does well to answer, rather than trying to prove that God is not Jesus.
* Walter Martin, Kingdom of the Cults, Expanded Anniversary Edition, October 1997, Bethany House Publishers, p. 123. "While the members of the [NWT] committee have never been identified officially by the Watchtower, many Witnesses who worked at the headquarters during the translation period were fully aware of who the members were. They included Nathan H. Knorr (president of the Society at the time), Frederick W. Franz (who later succeeded Knorr as president), Albert D. Schroeder, George Gangas, and Milton Henschel (currently the president)."