What do we mean by "Absolute Truth?"

The sky: blue today, gray tomorrow.
What do we mean by Absolute Truth?
It might help to look at a few statements from the Tenth Canto of Srimad-Bhagavatam:
"Everyone is searching after the truth. That is the philosophical way of life.
The demigods give information that the Supreme Absolute Truth is Kṛṣṇa. One who becomes fully Kṛṣṇa conscious can attain the Absolute Truth. Kṛṣṇa is the Absolute Truth.
Relative truth is not truth in all the three phases of eternal time. Time is divided into past, present and future. Kṛṣṇa is Truth always, past, present and future.
In the material world, everything is being controlled by supreme time, in the course of past, present and future. But before the creation, Kṛṣṇa was existing, and when there is creation, everything is resting in Kṛṣṇa, and when this creation is finished, Kṛṣṇa will remain.
Therefore, He is Absolute Truth in all circumstances.
If there is any truth within this material world, it emanates from the Supreme Truth, Kṛṣṇa. If there is any opulence within this material world, the cause of the opulence is Kṛṣṇa. If there is any reputation within this material world, the cause of the reputation is Kṛṣṇa. If there is any strength within this material world, the cause of such strength is Kṛṣṇa. If there is any wisdom and education within this material world, the cause of such wisdom and education is Kṛṣṇa.
Therefore Kṛṣṇa is the source of all relative truths.
" (Srimad-Bhagavatam, (10.2.26)
For those unfamiliar with the concept, it may be difficult to grasp how a single person can contain or "be" all of reality: this world is full of relative truths, and Krishna is a different kind of person than we're used to thinking about.
Here’s an example of a "non-absolute," or relative truth:
"The sky is blue."
That may be true—if it’s daytime and there aren’t any clouds—but the sky won’t be the same color tonight and may not be the same color tomorrow. And even if it’s blue here, it’s not blue everywhere.
That statement is true, then, in a relative way—relative to time and space.
There are unlimited relative truths, but there is only one Absolute Truth. That’s why we capitalize the "A" and the "T."
Also, it isn’t possible to meditate on relative truths forever. The most pleasant "truths"—if they’re not absolute—either stop being true, or you get sick of them after a while.
But meditating on the Absolute Truth can make anyone fearless, ecstatic, and always eager for more:
tusyanti ca ramanti ca . . .
"The thoughts of My pure devotees dwell in Me, their lives are fully devoted to My service, and they derive great satisfaction and bliss from always enlightening one another and conversing about Me."

