It is often stated within the Christian Church that Noah built the Ark for 120 years, based on 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.” (my emphasis)
Here, in my opinion, the Lord is speaking of the life span of humans. There is no mention of the Ark. After the Flood, the life span of mankind decreased steadily. In fact, Moses lived to be exactly 120 years old.
Let’s look a little closer at Scripture. In Genesis 5:32 we are told that Noah was 500 years old when he fathered Shem, Ham and Japheth. In Genesis 6:4-6 and following we are told that there were giants and wicked men on the earth. It grieved the Lord that He had created man. As a result in Genesis 6:13 the Lord announced the end of all flesh on earth.
Assuming this Scripture is in chronological order, after this (Genesis 6:14-22), the Lord gave Noah instructions for building the Ark. Then in the 600th year of Noah’s life, he, his wife and his sons and his son’s wives entered the ark. (Genesis 7:11-13) Here is where we run into a problem. Noah fathered his three sons beginning at age 500. Then the Lord gave instructions for building the Ark. At age 600 the Flood came. There is not room for 120 years.
We are not told how long it took Noah to build the ark in Scripture. We need to teach from the Bible! Not what your old pastor preached, or what your favorite professor at Bible college told you. Look at the Bible before passing on tradition!
By the way, the three sons of Noah are frequently referred to as Shem, Ham and Japheth, as stated in Genesis 5:32. However, by reading Genesis 10 and 11 and applying logic, it is evident that the order of birth was Japheth, Shem and Ham.
Read and teach the Bible. Books, lessons and ideas of men are sometimes very good, but are not the inspired Word of God. Let’s abstain from teaching tradition.
“But in vain they do worship me, teaching for doctrines the commandments of men. – Matthew 15:9
Praise the Lord for His perfect, Spirit inspired Word that we have been blessed to receive, even after thousands of years! May His name be praised forever!