25 Methuselah lived one hundred and eighty-seven years, and begot Lamech.
26 After he begot Lamech, Methuselah lived seven hundred and eighty-two years, and had sons and daughters.
27 So all the days of Methuselah were nine hundred and sixty-nine years; and he died.
28 Lamech lived one hundred and eighty-two years, and had a son.
29 And he called his name Noah, saying, “This one will comfort us concerning our work and the toil of our hands, because of the ground which the Lord has cursed.”
30 After he begot Noah, Lamech lived five hundred and ninety-five years, and had sons and daughters.
31 So all the days of Lamech were seven hundred and seventy-seven years; and he died.
32 And Noah was five hundred years old, and Noah begot Shem, Ham, and Japheth.
Many ancient and modern commentators have interpreted the name Methuselah as meaning “When he dies, it shall be sent.” If this suggestion is correct (and there is at least a possible basis for it), then a justifiable inference is that Enoch, the prophet of coming judgment had received—at the time of the birth of this son—a special revelation concerning the coming judgment of the great Flood. God, however, promised him that it would not come as long as Methuselah lived; and Enoch gave him a name to commemorate that prophetic warning and promise. This may possibly be the significance of the fact that Methuselah lived longer (969 years) than any other man in history whose age was recorded. “God is long-suffering to usward, not willing that any should perish, but that all should come to repentance” (2 Peter 3:9). As He is long-suffering toward godless men today, so He was long ago, “when once the long-suffering of God waited in the days of Noah, while the ark was preparing” (1 Peter 3:20). — Morris, pages 159-160.
Lamech (as well as Adam, Abel, and Enoch) was undoubtedly one of those in Peter’s mind when he spoke of “the times of restitution [or ‘restoration’] of all things, which God hath spoken by the mouth of all his holy prophets since the world began” (Acts 3:21). Noah, as the one who would by his ark preserve life as the cursed earth was being “cleansed” by the waters of the Flood, was only a precursory fulfillment of Lamech’s prophecy, of course. The promised Seed was still future, but in Him and His promised coming were true “rest” and “comfort.”
Lamech, like all the other patriarchs, “began sons and daughters” in addition to Noah. It seem probable that these brothers and sisters of Noah must have perished in the Flood. Moreover, there must have been many others in the Sethite line that also perished, since it could hardly have been only the Cainites who had begun to “multiply on the earth” (Genesis 6:1). Thus, the wickedness and corruption which had become rampant had affected both branches of the human family by this time, except probably for the godly remnant in the direct line from Enoch to Noah.
It may even have affected Noah’s family, though of this we cannot be sure. We are told only of his three sons who survived the Flood; but it seem rather likely that he also, like the others, “began sons and daughters,” particularly since the five-hundred-year age at which Shem, Ham, and Japheth began to be born is more that three hundred years older than the age at which any of the other named members of the patriarchal line were born. The reason for mentioning three sons by name (rather than only Shem, the next in the prophetic lineage) is that these were the ones in his family who elected to go with him into the Ark and who would, therefore, become the progenitors of the post-Flood nations. — Morris, page 161.
Although sin prevented Adam and Eve from experiencing the pre-Fall ideal of “strolling” in most intimate physical proximity to God, the possibility, nonetheless remains open to man to experience that more fundamental spiritual proximity to God—which “proximity,” or “connection,” is perhaps best denoted by the English term “relationship.”
The hope of experiencing this pre-Fall ideal completely via not just spiritual, but also physical interaction with God (i.e., “walking” with Him in unrestricted proximity) is further highlighted in connection with Noah, whose father, Lamech (not the same as in Genesis 4:23), bases his son’s name in the expectation that Noah “will give us rest from the ground that God has cursed.” The clear messianic tenor of this statement is evident both from the name Noah (which derives from the same theologically-charged root meaning “to give rest” used to describe man’s initial state in Genesis 2:15—as well as from the specific reference to the ground that God cursed—which same terminology is used prior to this only in Genesis 3:17. Though the reason for this expectation concerning Noah is unstated (and hence not the point of the narrative), it is important to remember that the “messianic” hope is at this point still imminent—no less so, in light of what God has so far revealed, than it was for Eve when she expressed the similar expectation that her first-born son Cain was the promised human-divine Seed who would restore mankind to their pre-Fall ideal (Genesis 4:1). — Wechsler, pages 129-130.