To the choirmaster: to Jeduthun. A Psalm of David.

1   I said, “I will guard my ways,
    that I may not sin with my tongue;
  I will guard my mouth with a muzzle,
    so long as the wicked are in my presence.”
2   I was mute and silent;
    I held my peace to no avail,
  and my distress grew worse.
3     My heart became hot within me.
  As I mused, the fire burned;
    then I spoke with my tongue:
4   “O LORD, make me know my end
    and what is the measure of my days;
    let me know how fleeting I am!
5   Behold, you have made my days a few handbreadths,
    and my lifetime is as nothing before you.
  Surely all mankind stands as a mere breath! Selah
6     Surely a man goes about as a shadow!
  Surely for nothing they are in turmoil;
    man heaps up wealth and does not know who will gather!
7   “And now, O Lord, for what do I wait?
    My hope is in you.
8   Deliver me from all my transgressions.
    Do not make me the scorn of the fool!
9   I am mute; I do not open my mouth,
    for it is you who have done it.
10   Remove your stroke from me;
    I am spent by the hostility of your hand.
11   When you discipline a man
    with rebukes for sin,
  you consume like a moth what is dear to him;
    surely all mankind is a mere breath! Selah
12   “Hear my prayer, O LORD,
    and give ear to my cry;
    hold not your peace at my tears!
  For I am a sojourner with you,
    a guest, like all my fathers.
13   Look away from me, that I may smile again,
    before I depart and am no more!”

(ESV)