Sufficient for a day

[CyrilSebastian]

In the Gospel of Saint Matthew, Chapter 6, Verse 34 states:

 Sufficient for a day is its own evil.       

  Please explain.

 

[cargau]

Tomorrow will have its own challenges, toils and perils.

 

[Pat_Payne]

I’ve heard it put like this: “Yesterday’s a cancelled check, tomorrow’s a promissory note. Only today is hard cash, and it’s up to you to spend it wisely.”