Christ’s comments about the days of Noah are made to emphasise what he has said in verse 36 – no one knows the day and the hour in which the Son of man will appear. That day will come as a complete surprise to those living at the time.
The flood is a historic event, but is also a dreadful scene to make us think, to help us imagine what it is to have failed to respond to God’s warning. Of course Christ speaks of these things because he wants us to respond. He wants us to take these warnings seriously and to escape the final judgment. He is sympathetic to our predicament, even though we are guilty and entirely deserving of what is about to come. The first thing that happens in the heart of someone who is going to seek the Lord is a sense of their danger and the need to act decisively. We are comfortable with our sinful lifestyles, and can see no danger in continuing with them. We think we can afford to ignore the gospel, and to bolster ourselves in that point of view to are ready to ridicule the message and the messengers, saying, ‘Where is the promise of his coming? for since the fathers fell asleep, all things continue as they were from the beginning of the creation’ (2 Peter 3:4). That attitude is a snare. It lulls us to sleep and allows us to subdue any sense of alarm in us. But a sense of alarm would, in this situation, be our greatest friend.
The preacher’s task is not to understate the danger men and women are in. That danger is great, and needs to be expressed in solemn terms. He knows that many will push away the message, but he must ignore that and continue to stress the urgency, whether people will listen or not. Certainly, he wants people to respond, but if they will not he has discharged his duty, and they are responsible for their own destruction.