So why were most of Noah's family so violent and wanted to kill Noah, given that the people who drowned in that particular flood were all members of Noah's family, including his grandparents (Gen 5:27) and his widowed mother (Gen 5:31) and his aunts & uncles & cousins (Gen 5:26) and his brothers & sisters (Gen 5:30) and his hundreds of other children & grandchildren born before and after Mrs Noah gave birth to triplets at aged 500 "years" old? And is that why Noah & Abraham & Moses etc never went to heaven (John 3:13)?
First, No one was offered heaven before Jesus died. This is why even King David did Not ascend - Acts 2:34 and John B.- Matt.11:11.
Adam and Eve were offered 'everlasting life on a beautiful paradisical Earth' as long as they did Not break God's Law.
Jesus informs us that humble 'meek people will inherit the Earth ' - Psalms 37:9-11; Matthew 5:5.
Heaven or the heavenly calling is only offered to some people like those of Luke 22:28-30; Daniel 7:18.
Lots of people of Genesis chap. 5 died before Noah ( notice the words ' he died ') such Methuselah 'died' in verse 27; Noah's father Lamech 'died ' in verse 31.
Mrs. Lamech could have already died and Lamech could have already been a widower.
Remember: It took about 50 years to build that Ark, so many more relatives or non-relatives could have already died before the Flood.
Noah was a preacher and Not just an Ark builder to the message about God being determined to end that ungodly world and it fell on deaf ears, so to speak.
That violent world ( Genesis 6:11) would have killed off all righteous people including Noah and family.'
That would mean there would be No one left righteous on Earth.
That 'Day of Judgement ' cleaned and cleared things up, and allowed for us to be born and think who we would like as Sovereign over us.
By saying Noah was 500 years old when he begat three sons does Not mean triplets.
Remember: before the Flood the life span was a figurative ' day ' of 1,000 years with Methuselah living 969 years of age before he died.
In other words, No one would or could live more than age1,000.