Born in the latter days of Adam, Methuselah would have heard the old man speak directly of the days in the garden, and of the sorrow of being expelled from it. He saw a world already falling into deep sin almost a millennium before the Great Flood.
The fact that the Sethite line is separate from the line of Cain leads the reader to assume that those who at least knew about God directly, such as with first hand stories, would be in a better relationship with Him.
Being very old in his grandson Noah's time, Methuselah may have been of very little influence on him. His son Lamech probably took charge of the family affairs when the ark was being built. Sadly, Lamech died before the Flood, seven years before his father.
The name Methuselah is a compound word that can be understood in different ways. Because of the first letters "MT," many believe that this is a shortened form of "MUT" (or "muth," meaning death). The root of the ending of his name, "shelech" means "to send". This yields: "Dying, it shall be sent."
However, MTU -- Methu -- may be a form of MTI, meaning "When" leading to "When shall it be sent?" Together, these might mean "When he dies, it shall be sent."
The most likely meaning of the name is "Man of the sword" since the word "MT" denotes a male adult. The word "Shelech" means "sword" or "dart" from the idea of extension (like being thrust out). In all likelihood, the prophet Enoch used his son's name to tell those who would listen that trying times were coming.
He would grow up the son of the greatest prophet of the ancient world -- his father -- who would preach a message of coming judgment for three hundred years before disappearing. Some say his very name was a prophecy for coming judgment (see Etymology above). Such an upbringing may have led to postponing a family, for he became father to Lamech at 187, almost three times what was expected.
When he was 243 years old, Adam died at the age of 930. Though some people from the early days may have lived into these days, those of record would begin holding Adam's record of "oldest man alive" 130 years later when his grandson Enos would take the title and hold it for 80 years. Methuselah would only hold the title for seven years, when he surpassed his grandfather Jared who had died at age of 962.
Methuselah would name his son "Lamech," the name of the notorious murderer of the Cainite line. The name Lamech means "Powerful," lending to the spirit of the times of which his father Enoch was preaching in those days. It would be another 182 years before the birth of Noah, whose name was at least a prayer for relief, for Noah means "rest." He would live to see his great-grandchildren help their father construct the ark in the century before the flood, dying in that year at the age of 969.
Death and Legacy
Methuselah would die in the "year of the world" 1656 or 1657, depending on how one counts the years. This was the year of the Great Flood that killed all of mankind except his grandson Noah and those within the ark. Given the fact that the flood began in the second month of the year, the world's oldest man may have died only weeks before the flood began.
Methuselah was the sixth in the line of Sethites that preserved the righteous bloodline through a period that was becoming more dangerous by the day. His grandson Noah would be chosen by God to save some of mankind -- only eight -- of whom the earth would get a new start. Having grown up hearing Adam speak, it is reasonable to think he would have preserved those stories for his great grandchildren: Japheth, Shem, and Ham.
The detail in these accounts appears to have been recorded in some way, later to be used by Moses as source material when God guided him to collect them all for His people.