Methuselah is known as the longest living person in the Bible.  We read in Genesis 5:27, “And all the days of Methuselah were nine hundred sixty and nine years: and he died.”  969 years!  While we do not read much about this man, we do know that he was the son of Enoch, the father of Lamech, and the grandfather of Noah.  We read this in Genesis 5:25-29, “And Methuselah lived an hundred eighty and seven years, and begat Lamech: And Methuselah lived after he begat Lamech seven hundred eighty and two years, and begat sons and daughters: And all the days of Methuselah were nine hundred sixty and nine years: and he died. And Lamech lived an hundred eighty and two years, and begat a son: And he called his name Noah, saying, This same shall comfort us concerning our work and toil of our hands, because of the ground which the LORD hath cursed.” 

It is logical to think that both Methuselah and Lamech were alive during the time that Noah built the ark.  However, it is also logical to think that they both died before the flood began, instead of drowning in the flood waters. 

Let’s consider Genesis 7:1-5, “And the LORD said unto Noah, Come thou and all thy house into the ark; for thee have I seen righteous before me in this generation. Of every clean beast thou shalt take to thee by sevens, the male and his female: and of beasts that are not clean by two, the male and his female. Of fowls also of the air by sevens, the male and the female; to keep seed alive upon the face of all the earth. FOR YET SEVEN DAYS, and I will cause it to rain upon the earth forty days and forty nights; and every living substance that I have made will I destroy from off the face of the earth. And Noah did according unto all that the LORD commanded him.”  Surely Methuselah and Lamech were righteous men, yet the Lord singularly called Noah and his family righteous.  This would indicate that Methuselah and Lamech were already dead by this time. Many have speculated that this seven-day period of waiting for the flood was a time for mourning for Methuselah and Lamech before the flood began. 

Methuselah is mentioned in Adam’s genealogy in 1 Chronicles 1:3 and he is mentioned as Mathusala in the genealogy of Christ in Luke 3:37, “Which was the son of Mathusala, which was the son of Enoch, which was the son of Jared, which was the son of Maleleel, which was the son of Cainan.”  (CC)  (620.6)