Who was Methuselah?
The Torah tells us not much about him. What does the Talmud and the Rabbis say about Methuselah?
According to Sukkah 52b, one of the seven shepherds mentioned in Micah 5:4 is Methuselah who, along with Adam and Seth, is to the right of David.
According to Sanhedrin 108b (commenting on Genesis 7:10), the Deluge was delayed seven days for the mourning over the death of the righteous Methuselah.
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Methuselah appears in two important Jewish works from the 3rd and 2nd centuries BC. In the Book of Enoch, Enoch (as the narrator) tells Methuselah of the coming worldwide flood and of the future Messianic kingdom. He is known having a great sword (Sword of Methuselah) that conquers evils and ghosts. The Book of Jubilees names Methuselah's mother and his wife – both are named Edna – and his daughter-in-law, Betenos, Lamech's wife.
The 17th century midrashic Sefer haYashar ("Book of Jasher") describes Methuselah with his grandson Noah attempting to persuade the people of the earth to return to godliness. All other very long-lived people died, and Methuselah was the only one of this class left. God planned to bring the flood after all the men who walked in the ways of the Lord had died (besides Noah and his family). Methuselah lived until the ark was built, but died before the flood, since God had promised he would not be killed with the unrighteous. The Sefer haYashar gives Methuselah's age at death as 960 and does not synchronize his death with the flood.