If you do not believe the doctrine of the Trinity, and favor another view yourself, I am going to give you some free advice. I am going to tell you exactly what you need to do in order to defend your non-Trinitarian position as a superior alternative to the Trinitarian view. I know, this is very generous of me, but in the interests of full disclosure I think it only fair to make this information available to the opponents of the doctrine of the Trinity.

1. Refute one or more of the essential propositions of the doctrine of the Trinity.

In my outline study of the biblical basis of the doctrine of the Trinity, I explain that the doctrine is simply a systematization of six core propositions that are all based directly on the teaching of the Bible:

1. There is one God (i.e., one proper object of religious devotion).
2. This one God is a single divine being, called Jehovah or Yahweh in the Old Testament (the LORD).
3. The Father of our Lord Jesus Christ is God, the LORD.
4. The Son, Jesus Christ, is God, the LORD.
5. The Holy Spirit is God, the LORD.
6. The Father, Son, and Holy Spirit are each someone distinct from the other two.

In order to defend an alternative position, you must refute at least one of these premises, or, you must show that all six of these propositions are consistent with another theological position besides the Trinity. I do not think the latter is possible, and in fact I do not know of any non-Trinitarian theology that affirms all six propositions (at least, not without some heavy equivocation). So, for all practical purposes, if you’re going to defend another view in place of the Trinity, you’ll have to refute one of the above premises.

2. Present a clear alternative to the doctrine of the Trinity.

Constantly carping at things about the Trinity that you don’t like, can’t understand, and won’t accept is not enough. You must tell us what we should believe instead. Your position must be specific and cover the same basic issues that are addressed in the doctrine of the Trinity.

3. Identify the religion associated with that alternative to Trinitarian Christianity.

It’s no good telling us that you believe X, Y, and Z instead of the Trinity, if this “alternative” is your own private confection of beliefs. I say this because the true doctrine of God will be held by a community of believers in Jesus Christ—by the church. Theologies do not exist in a vacuum, or in isolation. You are either part of a church that teaches the theology you espouse, or you are picking and choosing what you will believe from others and not committing yourself to a way of life that puts a set of teachings into practice. Jesus Christ said that he would be with his people until the end of the age as they engaged in the work of making disciples, baptizing and teaching them (Matt. 28:19-20). So, what people today are Christ’s people? This question has become acutely relevant in the Internet age, in which many individuals appear to be one-man religions, trolling the Web to attack orthodox Christian beliefs (often loudly and aggressively) but who are unprepared to identify a belief system they accept and a community that represents that belief system.

4. Show that your alternative theology does not suffer from the defects you claim to find in Trinitarianism.

For example:

a. If you criticize the doctrine of the Trinity for developing in the fourth century, identify the religious tradition or movement that predated the fourth century that you think had—and has—the truth.

b. If you criticize the doctrine of the Trinity for its use of extrabiblical language, show that your theology consistently avoids the use of all extrabiblical words. This is much harder than just about all anti-Trinitarians think.

c. If you criticize the doctrine of the Trinity for being influenced by non-Christian philosophy or religion, show that your theology is completely free of such influences. Again, this is easier said than done.

d. If you criticize the doctrine of the Trinity for being difficult to understand, show that your theology is free of anything incoherent, confusing, paradoxical, or mysterious.

5. Demonstrate that your theology explains the full range of biblical information better than the doctrine of the Trinity.

This means showing that your view accounts for a wider range of biblical material, based on sound exegesis of the texts, with a minimum of ad hoc reasoning. In other words, it is not enough to argue that certain texts might be translated so as to avoid the Trinity, or that other texts need not be interpreted in a Trinitarian fashion. Rather, you must show that your non-Trinitarian view is the best reading of more biblical texts than can be claimed on the Trinitarian side.

Of course, everyone is likely to run into a text or two that is more difficult to cohere with their position, but the right view will have fewer of these difficulties.

Note: All such argumentation will have to contrast the anti-Trinitarian alternative with the doctrine of the Trinity as it is actually taught in serious works of theology, not your own over-simplistic or fractured impression of what the doctrine means.

Good luck!