Now is all you have
Bernie Glassman in The Dude and the Zen Master, which is about as charming as it sounds. On p. 32-38 of my copy:
In practice, it's hard to grasp that right here, where you're standing, is it.
You can hear it over and over, but there's a piece of you that doesn't believe it. Instead, we work to get over there. And once we get over there, we reconsider: Oh no, this isn't it, so now I have to get over there.
Off we go again, trying to get to the next other shore. And once we get there, the whole thing starts again. At first I think, Oh, finally I got somewhere; now I'm happy. But after a while I say, No, this isn't it, I've got to get over there.
...
I've never met anybody who honestly says all the time, This is it. This shore, where I'm standing right now, is the place; whatever I need is right here. Such a person is fully in the moment, here and now, but I've never met anyone who's always like that. No matter how hard we try, situations come up that we'll want to separate from and leave behind us.
But if you are going somewhere else, let me say this much: at least change the boat and the oars. Say I get to the other side, what do I do? Well, I got here thanks to this beautiful boat with the set of oars, so I'll just hold on to them and carry them wherever I go. Isn't that weird?
Now I've got the burden of carrying around whatever got me here. Instead I get rid of it, and I'm free. Time passes and now I want to get to the next other shore. I'll probably need a new kind of boat and different oars, because maybe now the other shore is on the other side of the ocean and that requires a whole other mode of transportation.