Genesis 6:3

6:3 So the Lord said, “My spirit will not remain in humankind indefinitely, since they are mortal. They will remain for 120 more years.”

Genesis 6:5

6:5 But the Lord saw that the wickedness of humankind had become great on the earth. Every inclination of the thoughts of their minds was only evil all the time.

Genesis 6:13

6:13 So God said to Noah, “I have decided that all living creatures must die, for the earth is filled with violence because of them. Now I am about to destroy them and the earth.