I always find it interesting how so many non-believers use The Flood in just about any argument about God. I've seen it quite a number of times on this message board.
quote:
when he slaughtered millions of innocent people during the Flood, then regretted it, He realised just how stupid He was over this sin nonsense
If you're going to be using The Flood in your arguments, you might want to get the story right.
Genesis 6:5 "When the Lord saw how great was man's wickedness on earth, and how no desire that his heart conceived was ever anything but evil..."
This sounds like not so innocent people to me, in fact it sounds as if they are...well...evil.
Secondly, I'm not sure where you come up with the idea that God regretted wiping out everyone in the Flood. But if you are referring to Genesis 8:21 "When the Lord smelled the sweet odor, he said to himself: 'Never again will I doom the earth because of man, since the desires of man's heart are evil from the start; nor will I ever again strike down all living beings, as I have done.'", that isn't saying that he regretted doing it at all. It merely was making a statement or 'covenant' that he will not destroy all life because of the wickedness of man.
Since God had made this covenant with Noah, and we are unable to save ourselves because the desires of our hearts are evil from the start, it was up to God to save us. That's what he did by sending his Son as a sacrifice for the sins of the world.