Genesis 48:19-20

19But Jacob refused to change. He said, ‘I know, my son. I know what I am doing. Manasseh will also have many descendants who become a great nation. But his younger brother, Ephraim, will become even greater. Ephraim's descendants will become many great nations.’

20So Jacob blessed both of Joseph's sons that day. He said, ‘In your name Israel's people will give this blessing: “May God be good to you, just like he was to Ephraim and Manasseh.” ’ In this way, Jacob put Ephraim before Manasseh when he blessed them.