Worry in life is very much like a rear-view mirror when driving.

Oh sure, it can be very handy from time to time when changing lanes but most of the time, there isn't a damn thing you can do about what you see in it. And it can distract you from watching the road directly in front of you.

Delphi Temple Inscriptions:

Know Thyself
Nothing In Excess
Make a Pledge and Mischief is Nigh

γνῶθι σεαυτόν
μηδὲν ἄγαν
Ἑγγύα πάρα δ'ἄτη