The quote is from a book I picked up at the Getty Villa gift shop called Every Time I Find the Meaning of Life, They Change It by Daniel Klein. The full text of the relevant section is below.
The most exciting idea, to me, is that we can find infinite depth in each moment, if we choose to experience it. By reframing our concept of eternity as beyond time (rather than time infinitely stretching into the future) we can dip into eternity in each moment. (And that’s why past and future “don’t exist” - because Now is beyond time.)
Eternity isn’t trillions of years away; it’s hiding in the next inhale. Easier said than done. But still inspiring.