This quote is the famous last line from Fitzgerald's book, The Great Gatsby.

The line leading up to this famous quotes is as follows:

Gatsby believed in the green light, the orgastic future that year by year recedes before us. It eluded us then, but that's no matter — tomorrow we will run faster, stretch out our arms farther. ... And one fine morning —

The precise meaning of the final lines of the book are often interpreted differently, but all of them including a seeking of the unattainable.