|Lake Michigan beach, from some Michigan state park|
There's no need to talk about "absolute" truth when "truth" is enough. The word "absolute" adds nothing to "truth."
Consider the apostle Paul's statement in Philippians 4:8 - Whatever is true... think on these things. Paul does not write Whatever is absolutely true, because there is no need to. Truth is truth, and adding "absolute" to it contributes nothing.
I suspect that some began to use the term "absolute truth" in the face of creeping epistemological relativism. That is, when persons began to believe that Truth is relative, the word "absolute" was added for emphasis.
But it's not needed.
Philosophers do talk about "objective truth." I think that's more helpful, more clarifying. To call some truth "objective" means it is true independently of any human knowing subject. Take, for example, the statement The lights in the room are now on. If this statement is true, then it is objectively true; i.e., its truth is independent of whether or not anyone believes it to be true. Our beliefs do not make them objectively true.
If The lights in the room are now on is true, it means that the state of affairs (the lights in the room are on) is the case for anyone, even for those who believe the statement to be false. If someone thinks it is false that The lights in this room are now on, then they are simply wrong.
Take this statement: 1) John's ancestors all came from Finland. I'm using the name "John" to refer to myself. This makes the statement true. Of course it's not true that 2) Everyone's ancestors came from Finland. That statement is false.
If someone says, "For me statement 1 is false, and statement 2 is true, that's just plain absurd. Statement 1 is true, period. Statement 2 is false, period. While statement 1 refers to me, and is thus a subjective statement, the truth of that statement is not subjective. That would give us the absurd statement It's true for me that John's ancestors all came from Finland. This would be like saying, It's true for me that the earth orbits the sun.
Note the distinction between "truth" and "belief." Beliefs are not equivalent to truths. Beliefs can be either true or false. But this is a function of statements, not human subjectivity.