Iscool:
Show me in the Scriptures where the Holy Trinity is “formally defined”, ie. that God is One Divine Substance, yet three Distinct Persons who are all Divine Persons but are in a perfect communion of Love and thus so intimately related that there are “not 3 Gods” but One God.
Show me in the Sacred Scriptures where Christ, the Second Person of the Holy Trinity is formally defined as “a Divine Person” who has both a “Full Divine Nature” and “Full Human Nature” and those 2 Natures are not at odds or in confusion and both fully function in the Divine Person who is Christ.
The Bible does not speak on its own, it had to be interpreted by the Church, which St. Paul describes as the “pillar and Foundation of Truth” (cf 1 Timothy 3:15) and the Church doing the interpretation via the Church Fathers and Councils of the Early Church (Nicea 325, Constantinopile 381, Ephesus 431, and Chalcedon 451) were the “One Holy, Catholic and Apostolic Church” not your local protestant ecceslial community in backwoods America.
We believe in the Trinity because we can see it in the scriptures...If it wasn't there, we wouldn't believe it...
I can't say why you can't find the Trinity in the scriptures...Maybe it's a spiritual issue...