For the Jews require a sign This is explanatory of the preceding statement -- showing in what respects the preaching of the gospel is accounted foolishness At the same time he does not simply explain, but even goes a step farther, by saying that the Jews do not merely despise the gospel, but even abhor it. "The Jews," says he, "desire through means of miracles to have before their eyes an evidence of divine power: the Greeks are fond of what tends to gratify human intellect by the applause of acuteness. We, on the other hand, preach Christ crucified, wherein there appears at first view nothing but weakness and folly. He is, therefore, a stumblingblock to the Jews, when they see him as it were forsaken by God. To the Greeks it appears like a fable, to be told of such a method of redemption." By the term Greeks here, in my opinion, he does not mean simply Gentiles, but has in view those who had the polish of the liberal sciences, or were distinguished by superior intelligence. At the same time by synecdoche, all the others come in like manner to be included. Between Jews and Greeks, however, he draws this distinction, that the former, striking against Christ by an unreasonable zeal for the law, raged against the gospel with unbounded fury, as hypocrites are wont to do, when contending for their superstitions; while the Greeks, on the other hand, puffed up with pride, regarded him with contempt as insipid. When he ascribes it to the Jews as a fault, that they are eagerly desirous of signs, it is not on the ground of its being wrong in itself to demand signs, but he exposes their baseness in the following respects: -- that by an incessant demand for miracles, they in a manner sought to bind God to their laws -- that, in accordance with the dullness of their apprehension, they sought as it were to feel him out [1] in manifest miracles -- that they were taken up with the miracles themselves, and looked upon them with amazement -- and, in fine, that no miracles satisfied them, but instead of this, they every day gaped incessantly for new ones. Hezekiah is not reproved for having of his own accord allowed himself to be confirmed by a sign, (2 Kings 19:29, and 2 Kings 20:8,) nor even Gideon for asking a two-fold sign, (Judges 6:37, 39.) Nay, instead of this, Ahaz is condemned for refusing a sign that the Prophet had offered him, (Isaiah 7:12.) What fault, then, was there on the part of the Jews in asking miracles? It lay in this, that they did not ask them for a good end, set no bounds to their desire, and did not make a right use of them. For while faith ought to be helped by miracles, their only concern was, how long they might persevere in their unbelief. While it is unlawful to prescribe laws to God, they wantoned with inordinate desire. While miracles should conduct us to an acquaintance with Christ, and the spiritual grace of God, they served as a hindrance in their way. On this account, too, Christ upbraids them, (Mark 8:12.) A perverse generation seeketh after a sign. For there were no bounds to their curiosity and inordinate desire, and for all that they had so often obtained miracles, no advantage appeared to arise from them.

Footnotes

1 - There can be no doubt that Calvin refers here to an expression made use of by Paul in his discourse to the Athenians, Acts 17:27 Ei ara ge pselapheseian auton kai euroien (if haply they may feel him out and find him.) The allusion is to a blind man feeling his way The same word is employed by Plato, (Phoed. footnote 47, edit. Forster.) O de moi phainontai pselaphontes hoi polloi hosper en skotei, (In this respect the many seem to me to be feeling their way as it were in the dark.) -- Ed

For the Jews require a sign - A miracle, a prodigy, an evidence of divine interposition. This was the characteristic of the Jewish people. God had manifested himself to them by miracles and wonders in a remarkable manner in past times, and they greatly prided themselves on that fact, and always demanded it when any new messenger came to them, professing to be sent from God. This propensity they often evinced in their contact with the Lord Jesus; Matthew 12:38; Matthew 16:1; Mark 8:11; Luke 11:16; Luke 12:54-56. Many mss., instead of "sign" here in the singular, read "signs" in the plural; and Griesbach has introduced that reading into the text. The sense is nearly the same, and it means that it was a characteristic of the Jews to demand the constant exhibition of miracles and wonders; and it is also implied here, I think, by the reasoning of the apostle, that they believed that the communication of such signs to them as a people, would secure their salvation, and they therefore despised the simple preaching of a crucified Messiah. They expected a Messiah that should come with the exhibition of some stupendous signs and wonders from heaven (Matthew 12:38, etc., as above); they looked for the displays of amazing power in his coming, and they anticipated that he would deliver them from their enemies by mere power; and they, therefore, were greatly offended 1-Corinthians 1:23, by the simple doctrine of a crucified Messiah.
And the Greeks - Perhaps this means the pagan in general, in opposition to the Jews; see the note at Romans 1:16. It was, however, especially the characteristic of the Greek philosophers. They seek for schemes of philosophy and religion that shall depend on human wisdom, and they therefore despise the gospel.

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.

(25) For the Jews require a sign, and the Greeks seek after wisdom:
(25) A declaration of that which he said: that the preaching of the Gospel is foolish. It is foolish, he says, to those whom God has not endued with new light, that is to say, to all men being considered in themselves: for the Jews require miracles, and the Greeks arguments, which they may comprehend by their intellect and wisdom: and therefore they do not believe the Gospel, and also mock it. Nonetheless, in this foolish preaching there is the great power and wisdom of God, but such that only those who are called perceive: God showing most plainly, that even then when mad men think him most foolish, he is far wiser than they are, and that he surmounts all their might and power, when he uses most vile and abject things, as it has appeared in the fruit of the preaching of the Gospel.

For the Jews require a sign,.... The Jews had always been used to miracles, in confirmation of the mission of the prophets sent unto them, and therefore insisted on a sign proving Jesus to be the true Messiah; except signs and wonders were wrought, they would not believe; and though miracles were wrought in great numbers, and such as never man did, they remained incredulous, and persisted in demanding a sign from heaven, and in their own way; and it was told them that no other sign should be given them, but that of the prophet Jonah, by which was signified the resurrection of Christ from the dead; this was given them, and yet they believed not, but went on to require a sign still; nothing but miracles would do with them, and they must be such as they themselves pleased: the Alexandrian copy, and some others, and the Vulgate Latin version, read "signs", in the plural number:
and the Greeks seek after wisdom; the wisdom of the world, natural wisdom, philosophy, the reason of things, the flowers of rhetoric, the ornaments of speech, the beauties of oratory, the justness of style and diction; as for doctrines they regarded none, but such as they could comprehend with, and account for by their carnal reason, everything else they despised and exploded. Hence we often read (l) of , "the Grecian wisdom", or wisdom of the Greeks; which, the Jews say (m), lay in metaphors and dark sayings, which were not understood but by them that were used to it; the study of it was forbidden by them, though some of their Rabbins were conversant with it (n),
(l) T. Bab Menachot, fol 99. 2. Bava Kama, fol. 82. 2. (m) Maimon & Bartenora in Misn. Sota, c. 9. sect. 14. (n) Shalshelet Hakabala, fol. 25. 1. Ganz. Tzemach David, par. 3. fol. 31. 2.

For--literally, "Since," seeing that. This verse illustrates how the "preaching" of Christ crucified came to be deemed "foolishness" (1-Corinthians 1:21).
a sign--The oldest manuscripts read "signs." The singular was a later correction from Matthew 12:38; Matthew 16:1; John 2:18. The signs the Jews craved for were not mere miracles, but direct tokens from heaven that Jesus was Messiah (Luke 11:16).
Greeks seek . . . wisdom--namely, a philosophic demonstration of Christianity. Whereas Christ, instead of demonstrative proof, demands faith on the ground of His word, and of a reasonable amount of evidence that the alleged revelation is His word. Christianity begins not with solving intellectual difficulties, but with satisfying the heart that longs for forgiveness. Hence not the refined Greeks, but the theocratic Jews were the chosen organ for propagating revelation. Again, intellectual Athens (Acts 17:18-21, &c.) received the Gospel less readily than commercial Corinth.

For the Jews require a sign. Not merely miracles, such as the apostles worked, but a sign from heaven (Matthew 12:38). They said, "Let Christ come down from heaven, if he be risen."
And the Greeks seek after wisdom. While the Jews asked for a sign from heaven, the Greeks demanded a well-argued system of philosophy (Acts 17:18).
But we preach Christ crucified. Not merely Christ, but Christ Crucified; a Crucified Savior.
Unto the Jews a stumbling-block. Because they had an entirely different conception of the Christ. Yet it was predicted that he should be "a stone of stumbling" (Matthew 21:42).
Unto the Greeks foolishness. It seemed to the Greeks that a being who died so ignominious a death could not be divine.
But to them which are called. But to those who obey the gospel call, whether Jews or Gentiles, the Crucified Christ is found to be the power of God, and the wisdom of God. The gospel not only is found to be mighty, but wise in meeting the wants of the soul.
The foolishness of God. In one thing that men call foolishness, in Christ Crucified, there is greater wisdom than in all the philosophers, and though it seemed weakness of God to let Christ be crucified, yet the Crucified Savior is mightier than all the strength of men. If folly and weakness be of God, these will be wiser and stronger than men.

For whereas the Jews demand of the apostles, as they did of their Lord, more signs still, after all they have seen already; and the Greeks, or gentiles, seek wisdom - The depths of philosophy, and the charms of eloquence.