Here are the key Biblical passages referenced in the sermon.
Looking back on the Noah story:
7 So the Lord said, “I will blot out from the earth the human beings I have created—people together with animals
and creeping things and birds of the air, for I am sorry that I have made them.”
8 But Noah found favor in the sight of the Lord.
9 These are the descendants of Noah. Noah was a righteous man, blameless in his generation; Noah walked with God.
10 And Noah had three sons, Shem, Ham, and Japheth.
11 Now the earth was corrupt in God’s sight, and the earth was filled with violence.
12 And God saw that the earth was corrupt; for all flesh had corrupted its ways upon the earth.
13 And God said to Noah, “I have determined to make an end of all
flesh, for the earth is filled with violence because of them; now I am going to destroy them along with the earth.
14 Make yourself an ark of cypress[a] wood; make rooms in the ark, and cover it inside and out with pitch.
[Skipping the technical details of building and provisioning the ark.]
22 Noah did this; he did all that God commanded him.
After which the flood comes and everybody who was not in the ark dies. While Noah “did all that God commanded him,” he does not show the slightest concern about those he left behind. Did he care about them at all? Contrast that with what Abraham and Moses did when facing similar cases of God’s wrath.
20 Then the Lord said, “How great is the outcry against Sodom and Gomorrah and how very grave their sin! 21 I must go down and see whether they have done altogether according to the outcry that has come to me; and if not, I will know.”
22 So the men turned from there, and went toward Sodom, while Abraham remained standing before the Lord.[a] 23 Then Abraham came near and said, “Will you indeed sweep away the righteous with the wicked? 24 Suppose there are fifty righteous within the city; will you then sweep away the place and not forgive it for the fifty righteous who are in it? 25 Far be it from you to do such a thing, to slay the righteous with the wicked, so that the righteous fare as the wicked! Far be that from you! Shall not the Judge of all the earth do what is just?” 26 And the Lord said, “If I find at Sodom fifty righteous in the city, I will forgive the whole place for their sake.” 27 Abraham answered, “Let me take it upon myself to speak to the Lord, I who am but dust and ashes. 28 Suppose five of the fifty righteous are lacking? Will you destroy the whole city for lack of five?” And he said, “I will not destroy it if I find forty-five there. 29 Again he spoke to him, “Suppose forty are found there.” He answered, “For the sake of forty I will not do it.” 30 Then he said, “Oh do not let the Lord be angry if I speak. Suppose thirty are found there.” He answered, “I will not do it, if I find thirty there.” 31 He said, “Let me take it upon myself to speak to the Lord. Suppose twenty are found there.” He answered, “For the sake of twenty I will not destroy it.” 32 Then he said, “Oh do not let the Lord be angry if I speak just once more. Suppose ten are found there.” He answered, “For the sake of ten I will not destroy it.” 33 And the Lord went his way, when he had finished speaking to Abraham; and Abraham returned to his place.”
9 The Lord said to Moses, “I have seen this people, how stiff-necked they are. 10 Now let me alone, so that my wrath may burn hot against them and I may consume them; and of you I will make a great nation.”
11 But Moses implored the Lord his God, and said, “O Lord, why does your wrath burn hot against your people, whom you brought out of the land of Egypt with great power and with a mighty hand? 12 Why should the Egyptians say, ‘It was with evil intent that he brought them out to kill them in the mountains, and to consume them from the face of the earth’? Turn from your fierce wrath; change your mind and do not bring disaster on your people. 13 Remember Abraham, Isaac, and Israel, your servants, how you swore to them by your own self, saying to them, ‘I will multiply your descendants like the stars of heaven, and all this land that I have promised I will give to your descendants, and they shall inherit it forever.’”
14 And the Lord changed his mind about the disaster that he planned to bring on his people.
Abraham and Moses pleaded with God to change his mind, and in both cases it worked. God did not proceed with the planned slaughters. Why didn’t Noah ask God not to send the flood? And since he did not make such a plea, why is he “a righteous man? It is not enough to look out for yourself and your family. You have to care for all people.
This is not a new question. It was discussed by Rabbis in the middle ages.