Themes
Rash indeed is he who reckons on the morrow, or haply on days beyond it; for tomorrow is not, until today is past.
— Sophocles

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
Sophocles warns that counting on tomorrow, or the days beyond it, is rash. Tomorrow doesn't arrive until today has run out. So the sensible move is to treat today as the only time you truly hold.
Context reviewed