biblical truth= would be truth in the Bible
So, yes it does exist.
Is it part of the one truth?...absolutely it is.
It is not about what people call truth, it is about what is Truth. This is why Faith is such an important part of being a Christian.
And as your quote from the bible details the truth is sharp! It hurts peoples feeling very often, that is why we often recoil from it. I just noticed that the word truth actually contains the letters for the word hurt...interesting in itself.
"I have not written to you because you know not the truth, but because you know it, and that no lie is of the truth."
I am describing it in precision, as honestly as possible. I portray the quandry in words so that it is defined.
example: All men are mammals. All mammals are not men.
23 Being born again, not of corruptible seed, but of incorruptible, by the word of God, which lives and abides forever.
24For all flesh is as grass, and all the glory of man as the flower of grass. The grass withers, and the flower thereof falls away:
25But the word of the Lord endures forever. And this is the word which by the gospel is preached unto you.