I'm assuming that you are referring to the flood of Noah's Day.
YOU MAY HEAR: “God was cruel when he unleashed a flood that destroyed all mankind except for Noah and his family.”
THE BIBLE SAYS: God said: “I take delight, not in the death of the wicked one, but in that someone wicked turns back from his way and actually keeps living.” (Ezekiel 33:11) So the destruction of the wicked in Noah’s day brought God no pleasure at all. Then why did he do it?
The Bible answers that when God brought such judgments against ungodly people in times past, he was “setting a pattern for ungodly persons of things to come.” (2 Peter 2:5, 6) What pattern did God set?
First, God established that even though it pains him to destroy people, he does take note of cruel people who cause suffering and holds them accountable for their actions. In time, he will end all injustice and suffering.
Second, the pattern of God’s past actions establishes that God lovingly warns people before executing judgment. Noah was a preacher of righteousness, but most people ignored him. The Bible says: “They took no note until the flood came and swept them all away.”—Matthew 24:39.
Has God held to that pattern? Yes. For example, he warned his people Israel that if they turned to wickedness as the nations around them had, he would allow enemies to invade their land; destroy their capital, Jerusalem; and carry them off into exile. Israel did turn to wickedness—even carrying out child sacrifice. Did Jehovah act? Yes, but only after sending prophets to warn his people, again and again, to change their ways before it was too late. He even said: “The Sovereign Lord Jehovah will not do a thing unless he has revealed his confidential matter to his servants the prophets.”—Amos 3:7.
HOW YOU ARE INVOLVED: The pattern we see in Jehovah’s past judgments gives us hope. We can confidently look forward to God’s judgment of those who cruelly cause suffering. The Bible says: “Evildoers themselves will be cut off . . . But the meek ones themselves will possess the earth, and they will indeed find their exquisite delight in the abundance of peace.” (Psalm 37:9-11) What do you think about a judgment that relieves mankind of suffering? Is it cruel, or is it merciful?
New World Translation of the Holy Scriptures