لا يشرب من الفرات
He will not drink from the Euphrates.
The discussion assigns to Abu Hanifa priority for the direct literal mode of drinking from the river. The two companions include the recognized broader usage by which a person drinks water from that river even after it has been collected or transferred.
As in the wheat example, the disagreement concerns priority between a possible literal performance and a familiar expanded interpretation. It is not that “Euphrates” names multiple unrelated objects; it is how the action of drinking relates to the source of the water.