I believe the verse you are referring to is Genesis 6:3, “And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years.”  I encourage you to read this entire chapter.  You will find there God’s great disappointment in His most loved creation…man.  We read in Genesis 6:7, “And the LORD said, I will destroy man whom I have created from the face of the earth; both man, and beast, and the creeping thing, and the fowls of the air; for it repenteth me that I have made them.”  Because of the ungodliness of man, the Lord determined that He would destroy the world.  How would the Lord destroy the world?  He would send a great flood to destroy the earth and all that are in it…except for Noah and his family.

In Genesis 6:3, the Lord is not setting an age limit on man.  In fact, this verse shows the incredible grace of God.  Although He had determined to destroy the world, in His mercy he had determined that He would wait 120 years before the world’s destruction by this incredible flood.  The 120 years was actually a countdown to the time the Lord would send the flood to the earth.  Rather than continue to strive with men about their sinful condition, the Lord is warning that He would destroy the world in 120 years.  That gave Noah and his sons plenty of time to build and stock the ark before the flood.

Is there a time limit for man?  There is!  Men, in the beginning lived to be very old men.  Adam lived to be 930 years old.  Methuselah lived to be 969 years old (the oldest in the bible!).  Noah lived to be 950 years old.  After the flood, we find men gradually living shorter lives.  We then read in Psalm 90:10, “The days of our years are threescore years and ten; and if by reason of strength they be fourscore years, yet is their strength labour and sorrow; for it is soon cut off, and we fly away.”  This is telling us that the normal lifespan is 70 years old, although some might live even longer.  This is not a limit on man’s life, but a teaching on the normal man’s lifespan.  Some people live much longer, some die much sooner.

We just don’t know when the day of our death will be.  We read in Proverbs 27:1, “Boast not thyself of to morrow; for thou knowest not what a day may bring forth.”  None of us know what tomorrow may bring.  It may bring death to us.  That’s why we read in 2 Corinthians 6:2, “(For he saith, I have heard thee in a time accepted, and in the day of salvation have I succoured thee: behold, now is the accepted time; behold, now is the day of salvation.)”  If you have never put your faith in the Lord Jesus Christ as your savior ‘now is the day of salvation.’  Not tomorrow.  You don’t know what a day may bring forth!  Perhaps you will not live to see tomorrow.  It is so vital that you accept the Lord Jesus Christ as your savior today.  While we are not promised tomorrow…we are promised eternity.  What you do with the Lord Jesus will determine where you will spend eternity.  Acts 16:31 assures us, “Believe on the Lord Jesus Christ, and thou shalt be saved…”  Believe on the Lord Jesus Christ TODAY while there is still time.  (193.4)