Revelation 16:4

‘Thus says Yahweh, “By this you shall know that I am Yahweh: behold, I am about to strike the water that is in the Nile with the staff that is in my hand, and it will be turned to blood.

And the third angel sounded, and a great star fell from heaven, burning like a torch, and it fell on a third of the rivers and on the springs of waters.

Then I heard a loud voice from the sanctuary, saying to the seven angels, “Go and pour out on the earth the seven bowls of the wrath of God.”

I bear witness to everyone who hears the words of the prophecy of this book: If anyone adds to them, God will add to him the plagues which are written in this book.