For the Jews require a sign, and the Greeks seek after wisdom: For the Jews require a sign - Instead of σημειον, a sign, ABCDEFG, several others, both the Syriac, Coptic, Vulgate, and Itala, with many of the fathers, have σημεια, signs; which reading, as undoubtedly genuine, Griesbach has admitted into the text. There never was a people in the universe more difficult to be persuaded of the truth than the Jews: and had not their religion been incontestably proved by the most striking and indubitable miracles, they never would have received it. This slowness of heart to believe, added to their fear of being deceived, induced them to require miracles to attest every thing that professed to come from God. They were a wicked and adulterous generation, continually seeking signs, and never saying, It is enough. But the sign which seems particularly referred to here is the assumption of secular power, which they expected in the Messiah; and because this sign did not appear in Christ, therefore they rejected him.
And the Greeks seek after wisdom - Such wisdom, or philosophy, as they found in the writings of Cicero, Seneca, Plato, etc., which was called philosophy, and which came recommended to them in all the beauties and graces of the Latin and Greek languages.