Exodus 4:9

If in spite of these two signs they still will not believe you, and if they refuse to listen to what you say, take some water from the Nile and pour it on the ground. The water will turn into blood.

Exodus 1:22

Then Pharaoh commanded all his people: Every son who is born must be thrown into the Nile River. However, keep every daughter alive.

Jehovah then spoke to Moses: Tell Aaron, Take your staff and stretch out your hand over the waters of Egypt; its rivers, canals, ponds, and all its reservoirs. They will turn into blood. There will be blood everywhere in Egypt, even in the buckets of wood and stone pitchers.

Matthew 7:2

As you judge, so you will be judged. As you measure, it will be measured to you.

Treasury of Scripture Knowledge

Summary

Exodus 4:9

And it shall come to pass, if they will not believe also these two signs, neither hearken unto thy voice, that thou shalt take of the water of the river, and pour it upon the dry land: and the water which thou takest out of the river shall become blood upon the dry land.