A. Proverbs 27:1, Boast not thyself of tomorrow; for thou knowest not what a day may bring forth.

B. David's prayer to God before Israel shortly before he died. 1 Chronicles 29:15, For we are strangers before thee, and sojourners, as were all our fathers: our days on the earth are as a shadow, and there is none abiding.

C. Job 7:6, My days are swifter than a weaver's shuttle, and are spent without hope.

D. Psalms 39:4-6 - LORD, make me to know mine end, and the measure of my days, what it is; that I may know how frail I am. {5} Behold, thou hast made my days as an handbreadth; and mine age is as nothing before thee: verily every man at his best state is altogether vanity. Selah. {6} Surely every man walketh in a vain shew: surely they are disquieted in vain: he heapeth up riches and knoweth not who shall gather them.

E. Psalms 90:12 - So teach us to number our days, that we may apply our hearts unto wisdom. (entire chapter, especially verses 1-12)

F. Psalms 102:3, For my days are consumed like smoke, and my bones are burned as an hearth. (Because of the present trouble that has come upon David.)

G. Psalms 102:11, My days are like a shadow that declineth; and I am withered like grass. (Because of the present trouble that has come upon David.)

H. Psalms 103:15-18 - As for man, his days are as grass: as a flower of the field, so he flourisheth. {16} for the wind passeth over it, and it is gone; and the place thereof shall know it no more. {17} But the mercy of the LORD is from everlasting to everlasting upon them that fear Him, and His righteousness unto children's children, {18} To such as keep His covenant, and to those that remember His commandments to do them (Mankind should praise and bless God because He has blessed us, who are nothing but vanity and that which quickly fades away.)