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How Long to Build the Ark?

Q: Does the Bible say that it took Noah 100 years to build the ark?

A: It is not uncommon to hear a statement like, "Noah built the ark for 100 years." However, there is no mention in the Bible of a 100 year time span during which Noah did anything. One reference in the New Testament (I Peter 3:20) refers to the time during which Noah was building the ark, but does not give a specific time frame, ". . . when the patience of God kept waiting in the days of Noah, during the construction of the ark, in which a few, that is, eight persons, were brought safely through the water." A time span actually stated in the Bible which is often connected to Noah and his building the ark is the 120 years mentioned in Genesis 6:3, "Then the LORD said, 'My Spirit shall not strive with man forever, because he also is flesh; nevertheless his days shall be one hundred and twenty years.'"

A common inference made concerning those 120 years is that God intended to judge the world by causing the flood in 120 years. The reasoning then follows that Noah had those 120 years to construct the ark (thus, the source of the remark, "Noah built the ark for 100 years"). However, is that really the intent of God's statement in Gen 6:3? Let's consider the circumstances of Noah's life when God speaks to Noah about building the ark. What God says to Noah is recorded in Genesis 6:13-21, "Then God said to Noah, 'The end of all flesh has come before Me; . . . Make for yourself an ark . . . everything that is on the earth shall perish. But I will establish My covenant with you; and you shall enter the ark--you and your sons and your wife, and your sons' wives with you." This appears to be when God first tells Noah to build the ark, and notice, at that point in Noah's life, he not only had his 3 sons, they were married. There are two other chronological details of Noah's life which then allow us to narrow the time frame during which God must have commanded Noah to build the ark. "Noah was six hundred years old when the flood of water came upon the earth (Gen 7:6);" and "Noah was 500 years old, and Noah became the father of Shem, Ham, and Japheth (Gen 5:32)." These two figures indicate that Noah's sons were approximately 100 years old when the flood came upon the earth. This is verified with respect to Shem in Genesis 11:10 which states that he was 98 years old when the flood came. Since it appears that God first spoke to Noah about building the ark when his sons were not only born, but married, it had to have been significantly less than 100 years, perhaps only 60-70 years, from the time God commanded Noah to build the ark to the time God caused the flood.

It certainly is reasonable that Noah, his sons, and other hired hands (imagine how incredulous they were--until it began to rain!) could have built what was essentially a large 3-4 story building in 60 years. But, if indeed, there were just 60 or so years during which "the patience of God kept waiting in the days of Noah, during the construction of the ark," what is the significance of the 120 years mentioned by God in Genesis 6:3? It could be that God simply "waited" 60 years before telling Noah to begin building the ark, thus, when another 60 years had passed, the ark was ready and the 120 years "were up" so to speak. However, I think God had a different intent when referring to those 120 years. In Genesis 6:3 when He says, "My Spirit shall not strive with man forever, because he also is flesh; nevertheless his days shall be one hundred and twenty years." the context of God's statement seems to be more in reference to the lifespan of mortal man. In the days of Noah, people lived on average over 900 years. That average was sustained from Adam (930) to Noah (950). But, immediately after the flood, the recorded life spans of men dropped, and the trend is a dramatic decrease from Shem, who lived only 500 years (!) after the flood for a total of 600 years, to Jacob's son, Joseph, who lived a mere 110 years. There is no recorded lifespan exceeding 120 years after the era of Moses (who died at 120), except Jehoiada, the righteous priest largely responsible for the reformation during the days of Joash king of Judah. "Now when Jehoiada reached a ripe old age he died; he was one hundred and thirty years old at his death. And they buried him in the city of David among the kings, because he had done well in Israel and to God and His house (2nd Chronicles 24:15)." It would seem that his longevity, unique since Moses, was God's reward to him for his faithfulness. On the other hand, the legacy of man is "that every intent of the thoughts of his heart was only evil continually (Gen 6:5)." Could it be that what God intended to do by way of the flood was not only destroy all flesh with the earth, but intentionally bring down the lifespan of man from the extreme age in excess of 900 years in the pre-flood era to a maximum of 120 years in the post-flood age. God may very well have accomplished this through major changes on the earth as an aftermath of the flood.

Several lines of scientific evidence available today support this interpretation of Genesis 6:3.
1) The genetic information carried in our DNA is susceptible to mutation caused by several factors: physical, chemical and harmful forms of radiation. We know that aging definitely has a genetic component; thus, harmful mutations accumulating in the human genome (total DNA content) since the flood certainly is a possible physical explanation for the decrease in longevity.
2) As a result of the discoveries made by the Human Genome Project geneticists estimate only an astounding 2-3% of the total DNA actually encodes information for the synthesis of proteins. Even if we find ten times that amount to be functional in the future, what is the purpose of the other two-thirds of the genetic material? Perhaps all that "junk" DNA (see editors note at the end of this article) represents the relics of past genetic capacity, now lost due to millennia of accumulated mutations. Just as the strata of the earth are riddled with fossils of extinct organisms, so our chromosomes are riddled with "fossils" of extinct genes. The genetic capabilities of Seth and Methuselah are long gone.
3) Many scientists who study aging are surprised at what they are finding. Although, the average lifespan of humans has been increasing over the last century, especially due to advances in medical technologies, the maximum lifespan for humans has not increased. It appears that the maximum lifespan remains "pinned" at approximately 120 years of age! (Cf. Nov. 2003 issue of Discover.) Although some scientists are optimistic about increasing this maximum to even 150 years, such optimism is just that--mere hope.

Will we find a "glass ceiling" for the longevity for all humanity? Perhaps that ceiling has been imposed by the predetermined plan of our Creator Who back in the days of Noah decided that allowing sinful men to continue in lives of wickedness for multiple-hundreds of years was going to stop. It apparently did not take Noah 120 years to build the ark, it probably took only half that time, and yet today, God continues to be patient, allowing many to live much longer than 60 years in order that they might come to repentance and faith in the Lord Jesus Christ. But, He has apparently ordained a limit--120 years--at which time, "it is appointed for men to die once and after this comes judgment (Heb 9:27)." 
EDITOR'S NOTE:  New research called the ENCODE Project which was a "follow-up" the the Human Genome Project has actually determined the whole concept of JUNK DNA is incorrect.  We now know that at least 80% of human DNA is active; we just don't know what it all is doing--yet.

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