What was the actual problem with the people in the days of Noah?
The problem was not eating, drinking, or marrying, which are not wrong. Rather, they were so occupied with daily, mundane, materialistic activities that they continued until the day Noah entered the ark and remained unaware until the flood came and took them all away.
Les explains that Jesus, speaking in Matthew 24:37-39, compared the days of Noah to the coming of the Son of Man. The people were eating, drinking, marrying, and giving in marriage—activities that are not inherently wrong. Les points out that this was not the sin that brought God's wrath. The actual problem was that they were so occupied with these human, mundane events that they kept doing them until the day Noah entered the ark. They knew not until the flood came and took them all away. In Luke 21, Jesus even adds that they were building, further showing their absorption in daily materialistic activity.
For as in the days that were before the flood they were eating and drinking, marrying and giving in marriage, until the day that Noe entered into the ark,
More Questions
Was eating, drinking, and marrying a sin in the days of Noah?
Eating, drinking, marrying, and giving in marriage are not inherently wrong — there is nothing sinful about daily food and drink, or about marrying, weddings, and starting families.
Were eating, drinking and marrying the sin that brought God's judgment in Noah's day?
Eating, drinking, marrying and giving in marriage were not wrong in themselves, and they were not what brought God's wrath on the people of Noah's day.