Not one scripture of a vision, dream, or clear description wherein God is shown as three persons can be found. Nor can there be found a clear scripture where Jesus is called "God the Son," (equal to those declaring "God, the Father).
These are surely to be expected (if the trinity were true) just as "God the Father" is clearly and indisputably repeated many times in scripture.
God would not mislead us in something which means eternal life: "This is eternal life: their knowing you [Father], the only true God, and the one you sent forth: Jesus Christ." - John 17:1, 3.
Just as the essential knowledge of who the Messiah is is clearly repeated over and over in the scriptures, so should the equally essential knowledge of the different persons who make up the trinity should be so described in scripture [if true].
But neither these equivalents to "God the Father" nor a clear statement of the trinity is found anywhere in scripture.
So, rather than using the entire Bible as context, many believers in the trinity rely on a few selected, so-called 'proof-texts' which do not hold up under closer scrutiny:
Trinity 'Proof - Texts'
Clear, Scriptural Challenges For The Trinity Doctrine