Great Verse

I was praying about "understanding my human limits" (something Nora suggested I try to get a grasp on) and I found this verse... very applicable to me and my life. I need to know my limits and what I can reasonable do and feel in a day. and not "busy myself in vain." New Living says "all our busy rushing ends in nothing." Isn't THAT the truth???!!

Psa 39:4 - 6
"LORD, make me to know my end,
And what is the measure of my days,
That I may know how frail I am.
Indeed, You have made my days as handbreadths,
And my age is as nothing before You;
Certainly every man at his best state is but vapor.
Surely every man walks about like a shadow;
Surely they busy themselves in vain;