The Buddha recited the poem:
‘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 one fortunate attachment.’

Then the Blessed One rose from his seat and entered his dwelling.

— The Majjima Nikaya (The Middle Length Discourses of the Buddha)

Quotes

‘Unhappiness is not getting what we want: wanting it to be sunny when it’s cold, wet and rainy; people doing things that we don’t approve of having food that isn’t delicious and so on. Happiness is not the goal of life because it depends on so many things…

— The Venerable Ajhan Summedho