The Eternal Now by Ella Wheeler Wilcox

Time with his back against the mighty wall,
Which hides from view all future joy and sorrow,
Hears, without answer, the impatient call
Of puny man, to tell him of to-morrow.

Moral, be wise, and to the silence bow,
These useless and unquiet ways forsaking;
Concern thyself with the Eternal Now –
To-day hold all things, ready for thy taking.