I Peter 3:20. “Which sometime were disobedient, when once the longsuffering of God waited in the days of Noah, while the ark was a-preparing, wherein few, that is, eight souls were saved by water.”
God was patient. He gave mankind plenty of time to observe the building of the ark. They scoffed at Noah, of course, because there had been no such structure before. They laughed at the idea of rain, since to our knowledge there had been no such event before. The world and its climate were very different then.
My research leads me to believe it is possible, even likely, that it took about 55-75 years for Noah and his sons, who were adults and married when the building started. Here’s a link you can check out: https://answersingenesis.org/bible-timeline/how-long-did-it-take-for-noah-to-build-the-ark/
If it was indeed that long in building, then people had more than enough time to repent; to acknowledge God and His holiness, and to turn to Him for redemption.
How many people died in the Flood? One man, http://www.ldolphin.org/pickett.html, believes the world’s population at that time was somewhere between 5-17 billion, with an average around 10 billion. This number changes from person to person depending on belief in the literal interpretation of the Bible. It’s not really worth arguing about, in my opinion. The only reason I mention it is to get some idea of the immensity of the loss of life because of rebellion and sin against God.
For comparison’s sake, the two most populous countries today are India and China, with a combined population of about 2,900,000,000. Multiply that by 7 or 8, and you have an approximation of how many people perished in the Flood.
Mine is not a math brain. I have a hard time understanding 10 billion. I give you these stats for one reason only: To show you the incredible patience of God. The Bible uses the term longsuffering. In spite of Noah’s preaching, people scoffed and sneered at God’s warnings until, at last, the Ark was ready. When God shut the door, their time was up. No last-minute changes of mind.
Those who died in the Flood are mentioned as the ones to whom Jesus preached in Hades. Were there others there? I’m sure there were. We don’t know why they aren’t mentioned, or what Jesus’ sermon was about. Apparently God doesn’t need us to know. Perhaps those who died in the Flood are mentioned because of their long-standing rejection of His warnings.
Only eight souls were saved from the Flood: Noah, his wife, their three sons, and their sons’ wives. Our verse today says they were saved “by water.” The flood waters washed away sin and corruption and left a fresh new world in which to begin life anew. The obvious comparison is to the waters of baptism, which do not provide our salvation, but which indicate to God and other people that we have been saved by His grace, and are starting life anew.