For historical, classical Trinitarians, Jesus’ declaration that the Father is “the only true God” in John 17:3 was certainly a problem—not it seems, for modern-day apologists.
The noted German Protestant Heinrich Meyer in his New Testament Commentary notes that Augustine, Aquinas, Ambrose, Hilary, Beda, Thomas, Aretius, and several others forged the phrase “You [Father], the only true God” as “You [Father] and Jesus Christ, Whom you have sent, as the only true God.” To his credit Meyer calls this “a perversion of the passage, and running counter to the strict monotheism of John. Only One, the Father, can absolutely be termed the ‘the only true God’ (comp. ‘the one being over all God,’ Rom. 9:5), not at the same time Christ (who is not even in 1 John 5:20 the ‘only true God’).”
Yet, somehow, many Trinitarian apologists today think they have gotten around the problem posed by Jesus’ clear, strict unitary monotheism.
For example, Rob Bowman tries to get around the problem by asking JWs if Jesus is a true God or a false god. His answer:
“He can’t be a false god since that would mean the apostle John was guilty of falsely honoring Jesus as a god. Therefore he must be a true God. But Jehovah is the only true God. Therefore, Jesus must be Jehovah.”
Now this is clearly a false dichotomy. Jesus is neither “the only true God” nor “a false god.”
The third option is simply to declare what scripture makes repeatedly clear; “Jesus is the Christ, the Son of God” (John 20:31).
“To be called Son of God in the NT means that you’re not God.”
Furthermore, Bowman creates 1 Jehovah too many, according to the Shema.
Another well-known argument is to say that Jesus “is simply saying that the Father is the ‘only true God’—the only real or genuine God—as opposed to the many false gods and idols.” This is a tactic often employed when Trinitarians try to counter the numerical truth of “the one LORD,” Yahweh, of the Shema. But it’s self-evident that the God of the Bible is set over and against “the gods of the nations.” As Paul himself states in 1Cor 8:4-6, although there are many gods, for us Christians there is One God, the Father!
Finally, the Messianic Michael Brown who in his debate with Dale Tuggy said the verse “doesn’t say the Son is not” true God. As if just stating this makes it true! So no matter how many times and in how many ways modern-day Trinitarians try to subvert John 17:3, it’s impossible to circumvent the clear, unambiguous meaning of the text. These are indisputable facts whether you resort to corrupting the text, as the classical Trinitarians did, or continue to propagate illogical arguments.
 Rhodes, Reasoning From the Scriptures with the Jehovah’s Witnesses, 2009, pp. 254-55.
 “Trinity and Incarnation: in Search of Contemporary Orthodoxy,” Ex. Auditu; (7); 1991; p. 88-89.
 ibid., p 225.