I came across this poem from the Maha Kaccana Bhaddekaratta Sutta, composed by the Buddha:

Let not a person revive the past

Or on the future build his hopes,

For the past has been left behind

And the future has not been reached.

Instead with insight let him see

Each presently arisen state;

Let him know that and be sure of it,

Invincibly, unshakeably.

Today the effort must be made;

Tomorrow Death may come, who knows?

No bargain with Mortality

Can keep him and his hoards away.

But one who dwells thus ardently,

Relentlessly, by day, by night --

It is he, the Peaceful Sage has said,

Who has had one excellent night.

Apparently, the last line is usually translated as "Who has one fortunate attachment." but in this translation the "excellent night" refers to the day and night of fruitful meditation. Either way, it's a neat summary of the teachings.

I like it.