John 4:12 - Ellicott's Commentary On The Whole Bible

Art thou greater ...? — Again, the pronoun is the emphatic word, “Thou surely art not greater.” “The well used to satisfy the wants of the patriarch, and his household, and his flocks, and has come down from him to us. It is surely sufficient for all our wants.” This claim of Jacob as their father was through Ephraim and Joseph, and the well was part of “the parcel of ground that Jacob gave to his.son Joseph” (John 4:5). There was abundance of water near to it, but a patriarchal household could not depend for a necessity of life upon neighbours who may be hostile, and Jacob had dug this well in his own purchased plot. It was sacred, then, as the very spot where their asserted ancestor had digged his well and built his altar. There was an unbroken continuity in the history of the place, and it was prized the more because it was not so in the history of the people.