Genesis 6:13

And God said unto Noah, The end of all flesh is come before me; for the earth is filled with violence through them; and, behold, I will destroy them with the earth.

1. God spoke to Noah.
2. God told Noah of His intent to destroy mankind and the earth. (The term "destroy" appears to be used in two difference senses, for, clearly, the earth was not obliterated by the flood in the same way mankind was.)
3. God does not approve of mankind's use of violence.
4. God sometimes resorts to the use of violence in order to eliminate widespread wickedness and corruption from the earth.
5. Prophets may learn of God's intentions prior to the rest of mankind.
6. It seems wise to listen to what God's prophets have to say.