Genesis 49:3-4

Then Jacob said, “Reuben, you are my oldest son. You were born first. You were born at that time when I was a strong young man. You were the most important and the most powerful of all my sons. But then you went and did whatever you wanted, just like the wild water in the sea. You took one of my wives, and you slept with her, like a man sleeps with his wife. That was a wrong and dirty thing you did. You made me really shamed. So you will not be my most important son any more.”