Take Left and Right.
Take a car with a seat for the driver and a seat for the passenger. The seat for the driver is on the left side, the seat for the passenger on the right side.
We only know what we mean by contrast. Were there no passenger seat, were the vehicle much more like a motorcycle (just one seat total), it would be meaningless and nonsensical to describe the single seat as either a left or right seat, as there's only one seat.
However, if you give the vehicle back its second seat, the concept of Left-Right emerges, and not only does the concept emerge, but it necessarily emerges, because Left and Right necessarily go together. You'll never find one without the other. There is never a Left without a Right, or a Right without a Left.
In just the same way, self necessarily implies Self. In other words, if there is a finite self, then there must also be an infinite Self. There is never a self without a Self, or a Self without a self; the two necessarily go together; you cannot possibly have one without the other. You know you have one (you know the finite ego exists), so you (should) know you also have the other.
We're all really dead, and that's precisely how and why we're alive. Or, put differently, we're all really nothing, and that's precisely how and why we're something. You can't be something without being nothing, and you can't be nothing without being something. This is the only way Existence can function.
But the above is analogical. Analogies can point to the Truth, and they are certainly useful tools, but they cannot perfectly accurately represent or describe the Truth. The Truth lies beyond language, beyond what the egoic mind can know and understand. Only Truth can know Truth. Only God can know God. No ego has ever awakened to Truth. The ego is of time and space. Truth transcends time and space.
Adyashanti: Guided Self-Inquiry.
The Self, our true nature, is self-luminous, universal and primary to all phenomena. It is of neither space nor time, and therefore knows neither birth nor death. Only phenomena go in and out of existence; only phenomena change; only phenomena are of space and time.
Adyashanti: Guide Just Sit Meditation
In order for the Universal Mind to more deeply sit within its InfinityZeroness is for the finite mind to Relax. As long as you think there's a door, you'll only ever chase your tail - and you'll be chasing for eternity
Peace does not know time. Love does not know time. Wisdom does not know time. Like The Beatles said, "Love is All; Love is You."
Nirvana is not something you get in the future; only Now knows Now; only that which is not of time knows the timeless. The neurotic egoic processes, which carry an enormously powerful will to continue (not just to continue, but to continue well, also), are in a constant argument with what is. Everything is actually happening automatically, and there is ultimately nothing for you to let go of. Rather than neurotically constantly trying to change what is, if you let things simply be exactly as they are, no more and no less, the more you give up the Doer (that which is constantly Doing; in other words, that which is of time), the more Ultimate Reality comes into contact with Itself (in other words, the more the Source "sits" as the Source).
It's not a doing, and it's not a letting go. Letting go takes time; and again, everything is happening of itself, everything is happening automatically. There's actually nothing to let go of, and there's nothing you can do to awaken, because everything that is done takes a certain length of time. Your true nature is not of time; It does not know time and time does not know It. Only the Now can know the Now/only the Infinite can know the Infinite. The ego cannot know that which lies beyond it, just as a set of teeth cannot bite itself. Only that which lies beyond the ego can know that which lies beyond the ego.
Enter into the silent mind, "Who am I?" and then answer purely experientially (i.e. without hearing a peep from the egoic mind). The "answer" to the "question" needs to be more instant than instant; in other words, the questioning and answering needs to be a "single act". (I put "single act" in quotes because it's technically not an act, because all acts take time, and we are wanting to transcend time.) In order to achieve this "single act" of simultaneous questioning and answering, in order to transcend time, one must not act. There's nothing the ego can do to awaken.. So don't do. Just be. Do Nothing. Give up the Doer, give up Control. Fall into Grace, as Adyashanti puts it. Tomorrow Never Knows.