Trinity is a non-biblical term. Trinity is a human inference based on the Biblical data. But this cannot be an argument against the truth. We can use non-biblical terms in order to expose deviations of the Biblical truth and to express the Biblical truth.

The argument against trinity that the plurality of the divine name was merely a reflection of the kingly practice of the ancient times, is also invalid. There is no example in the writings of Moses where kings use plural names. No king that arose in Israel after the time of Moses is recorded to have spoken this way of himself. There is no clear evidence that even the uncircumcised kings of the surrounding pagan nations ever spoke this way. And even if they did, such practices and traditions cannot determine the nature of God. And hence it is only a weak argument against Christianity.

Some others argue that Trinity was not formulated until the fourth century. They argue that it was produced by the Roman catholic church through Constantine at the Council of Nicea in A.D. 325. But there was no "roman catholic church," until the end of the sixth century. The doctrine of the trinity and its essential terms were used by Tertullian long before Nicea. Though Constantine originally supported the trinitarian Athanasius, later he supported Arius. Arianism was dominating for many years. Any doctrine is the result of the progressive understanding of the Scripture and the historical development. The doctrine of the trinity was formulated also to counter the errors of Arianism and Modalism. Though the doctrine of trinity demands modification in the light of the Scripture, it was able to declare the deity of Christ. This guarded the church from many heresies in the course of many centuries.

Without doing any violence to the Bible and to human intelligence we can grasp God. It is very simple if we have the humility to understand that trinity is the revelation of God. Jesus is the most important revelation of God. At the same time God is invisible, inaccessible. Nothing is impossible with God. This view might contain some mystery.  Because it is difficult to comprehend this view. But it contains no contradiction. Incarnation of God in Jesus also does not contain any contradiction. Because there is no change in the nature of God here. It is the most prolonged and historically rooted revelation of God in human history. In incarnation God who is the pinnacle of perfection, was not trying to become anything new for His sake. Rather, God was lowering Himself for the sake of saving man.