John 4:48 - Coke's Commentary on the Holy Bible

Except ye see signs, &c.— Jesus said to him, and to them that were about him, "I perceive that though the Samaritans shewed so great a regard to my word, as to believe without the cogency of miracles, (see on John 4:41.) yet unless you see with your own eyes some remarkable and repeated miracles, you will not believe;)"—therebyjustly reproving him and them for that mixture of suspicion and slowness of faith which he discerned in their minds. See the preceding note. It seems necessaryto suppose some such reference, to illustrate the justice of this reproof; for in the general it was very reasonable to expect that Christ would work miracles in proof of his divine mission, as he himself plainly intimates elsewhere. SeeCh. John 15:24. Possibly the person now applying to him, might have made a declaration, that he would neverbelieve such things till he saw them with his own eyes. Christ might mean, by this reflection, to humble him, to shew him a specimen of his extraordinary knowledge as well as power, and thus to give increase and strength to his faith