In Genesis 6:3 God says, “My Spirit shall not always strive with man, for that he also is flesh: yet his days shall be a hundred and twenty years.”
In this verse, God set the minimum number of years that His people should live at 120. This verse could be written and read like this: “My Spirit shall not always strive with man, for that he also is flesh: yet his days shall be at least a hundred and twenty years.”
Some people misconstrue this Scripture to mean that Noah had 120 years to build the ark and gather the animals and preach until the flood came. These people say that God was saying that He was going to eradicate mankind from the earth after 120 years. This interpretation and reasoning makes no sense. It is contradictory. Because if God was saying that He was going to eradicate mankind from the earth after 120 years, then that would include Noah and his wife, their three sons, and their three sons' wives! And if God had decided to eradicate mankind from the earth, He would have just done it. He wouldn't have waited for 120 years!
What God was saying in Genesis 6:3 was that He is not going to let man live forever on this present earth in his present condition—yet he will be allowed to live at least 120 years. We know this verse is not talking about the maximum number of years a person is promised to live, because God says, “yet his days shall be a hundred and twenty years.” Also, if the 120 years that God was talking about was the maximum number of years that a person could live, then no one would live beyond the age of 120. However, we have plenty of people in the Bible and elsewhere that have lived to beyond 120.
Genesis 5:32 says that Noah was 500 years old when God made this pronouncement. Genesis 7:6 says that Noah was 600 years old when the flood of waters came upon the earth. This means that Noah built the ark, gathered the animals (with the supernatural help of God), and preached for 100 years—not 120. The 120 years mentioned in Genesis 6:3 has to do with God shortening the lifespan of man down to a minimum of 120 years, which took place gradually during the succeeding generations (Genesis 11:10–32). Previous to this, men were living into their 600's, 700's, 800's, and even 900's. However, during the succeeding generations down the line from Noah (who lived to be 950), men's lives were gradually shortened. Once we get past Abraham (who lived to be 175), Isaac (who lived to be 180), and Jacob (who lived to be 147), we have no record—in the Bible or elsewhere—of anyone living past the age of 140 (with the possible exception of Job; see “Job” below). This means that a person should live to be somewhere between 120 and 140 years of age.
Some Christians say that we are only supposed to live for 70 or 80 years. They use Psalm 90, verse 10, as their “proof text.”
“The days of our years are threescore years and ten; and if by reason of strength they be fourscore years, yet is their strength labor and sorrow; for it is soon cut off, and we fly away.”
A “score” is 20. So “threescore years and ten” would be 70 years, and “fourscore years” would be 80 years.
But to say that Christians can only live for 70 or 80 years is ridiculous, because there are many Christians, as well as many sinners, who live well beyond the age of 80. So this couldn't be what this Scripture is referring to.
This Scripture (the 90th Psalm) was written by Moses when the Israelites were wandering in the wilderness for 40 years waiting for all the people who were adults when they first reached the promised land, and refused to go in, to die. These people all died when they were about 70 or 80 because of their numerous sins of not believing God and murmuring and complaining during the first year when they came forth out of Egypt (Numbers 14:22–23, 26–35). They were consumed by God's anger and troubled by His wrath (verse 7). Their iniquities were set before God, and their secret sins were set in the light of His countenance (verse 8). Their days were passed away in God's wrath, and their years were spent “as a tale that is told” (verse 9). Their 70 or 80 years were labor and sorrow, and their life was soon cut off and they “flew away” (meaning their spirits and their souls left their bodies when they died (verse 10)).
We see here that the Israelites who were sentenced to die in the wilderness, only lived about 70 or 80 years. This was their sentence. This does not apply to us—unless we live in sin like they did. Then we may only live to about 70 or 80 years of age, instead of obtaining the promise of a minimum of 120 years. You can't just live any old way you want to and expect to live to be 120. You have to live according to the Word of God in order to receive the promises of God.
Here's a list of some of the people of the Bible who lived to 120 years of age and beyond, starting from the time of Abraham.
Jacob (Israel)........147....................Genesis 47:28
Jehoiada................130....................II Chronicles 24:15
Joseph, the son of Jacob, lived to be 110 (Genesis 50:26).
Joshua, the son of Nun, lived to be 110 (Joshua 24:29).
Miriam, the elder sister of Moses and Aaron, was old enough to watch and see what would happen to her three month old baby brother, Moses, when he was set among the reeds in the Nile River in a basket by their mother, and was picked up out of the water by Pharaoh's daughter. She then talked to Pharaoh's daughter and asked if she should go and get a “nurse” of the Hebrew women to breastfeed Moses. Pharaoh's daughter then told the girl to go and get one (Exodus 2:1–8). Miriam must have been an old enough girl to perform these tasks. Therefore, she must have been a number of years older than Moses and Aaron (who was three years older than his brother, Moses (Exodus 7:7)). Considering that she died in Numbers 20:1, near the end of the Israelites' wandering in the wilderness, she must have been at least in her late 120's, because Moses died at the age of 120 right at the end of the 40 years of wandering in the wilderness.
Mordecai (the Mordecai of the book of Esther who raised his cousin, Hadassah (Esther)) had been carried away from Jerusalem to Babylon (in the second deportation of Jews from Jerusalem to Babylon during the Babylonian Captivity) with the captivity which had been carried away with King Jehoiachin (Jeconiah, Coniah) of Judah by King Nebuchadnezzar II of Babylonia in 597 B.C. (Esther 2:5–7). If he was only an infant when he was carried from Jerusalem to Babylon, and since Esther became queen in the seventh year of King Ahasuerus I's reign (which was from 486 to 465 B.C.), Mordecai would have been at least 117 years old at the time Esther became queen (Esther 2:16–17).
Then, six years later, in the thirteenth year of King Ahasuerus I's reign, on Nisan 13th (which would be approximately April 2nd, 474 B.C. on our modern day Gregorian calendar), Haman sent letters into all the king's provinces to tell the people of the kingdom to kill all the Jews on Adar 13th (which would be approximately March 5th, 473 B.C. on our modern day Gregorian calendar) (Esther 3:7,12–13).
The Bible then records that the tables were turned, and on Adar 13th, the Jews ended up killing their enemies instead (Esther 9:1–5). The Bible then says that Mordecai lived for some time after this date (Esther 10). Therefore, Mordecai lived to be more than 124 years old.
Job had ten children (seven sons and three daughters) who were grown. Job 1:18–19 says,
“Thy sons and thy daughters were eating and drinking wine in their eldest brother's house: And, behold, there came a great wind from the wilderness, and smote the four corners of the house, and it fell upon the young men, and they are dead....”
Job's children are referred to as “young men,” meaning, “young adults.” Job's eldest son had his own house. Job's other nine children may have had their own houses also.
After Job went through a number of very serious trials, including having his ten children killed by Satan, he was delivered, and lived another 140 years seeing his sons and his sons' sons, even four generations (Job 42:16). This means that his age was 140 plus whatever age he was when his ten adult children died.
We don't know exactly when Job lived. But he could have lived after the time of Abraham, Isaac, and Jacob. This could fit because Job only lived 140 years after all his trials were over (Job 42:16). God, in essence, gave Job a “new” or “second” life (including ten more children) because of all that he had been through. And since after the time of Abraham, Isaac, and Jacob men's lives were now limited to about 120 to 140 years, his “new” or “second” life, so to speak, was then limited to 140 years.
Anna, the prophetess (Luke 2:36–37), was of a great age—and was still alive at the time the Bible mentions her! We don't know how much longer she lived before she died, but the Bible says that she had been married for 7 years, and had been a widow for 84 years. Considering that she was an adult, at least 20 years of age (see When Does a Person Become an Adult?) when she got married, she was at least 111 years old at the time that Joseph and Mary brought Jesus into the temple (20+7+84=111). (Some people, and some Bible translations, say that she was “an 84-year-old widow,” as opposed to “a widow for 84 years,” but this is incorrect.)