Faith comes from Hearing
Romans 10:17 (ESV) … “So faith comes from hearing, and hearing through the word of Christ.”
Paul mourns with Isaiah (Isa. 53:1) over the unreasonable unbelief of his people, for the gospel is not some new thing; it is rooted and grounded firmly in the Old Testament.
Faith cometh by hearing. It is only as the message is proclaimed that a response can be kindled. The supreme tragedy is that people refuse to hear. Israel refused to hear. The Lord Jesus again and again cried, “He that hath ears to hear, let him hear” (Matt. 11:15; 13:9, 43). Often, too, those who consent to listen fail to hear. The energizing power of the Word guarantees, however, that those who hear and respond have their faith quickened. Peter emphasizes a similar truth when he speaks of “being born again, not of corruptible seed, but of incorruptible, by the word of God, which liveth and abideth for ever” (1 Peter 1:23). So then, because there is power in the word of Christ for those who hear, Jewish unbelief is unreasonable.
Not only does the unique power of the Word make belief possible, but (b) the universal proclamation of the Word makes belief possible. Paul says, “But I say, Have they not heard? Yea verily, their sound went into all the earth, and their words unto the ends of the world” (v. 18).
Jewish unbelief is unreasonable not only because they could believe but because (2) they should believe. The Gentiles have embraced the gospel, Paul argues, and this fact alone should arouse the Jewish conscience. “But I say, Did not Israel know? First Moses saith, I will provoke you to jealousy by them that are no people, and by a foolish nation I will anger you. But Esaias is very bold, and saith, I was found of them that sought me not; I was made manifest unto them that asked not after me” (vv. 19–20). Paul cites Moses and Isaiah as witnesses that the Hebrew Scriptures themselves foretold the conversion of the Gentiles. The Jews should believe, if for no other reason, out of sheer jealousy of the fact that the Gentiles have stolen a march, so to speak, on them.[1]

[1] Phillips, J. (2009). Exploring Romans: An Expository Commentary (Ro 10:16–20). Kregel Publications; WORDsearch Corp.