Romans 10:19
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 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.
The no people and the foolish nation are the Gentiles, whom Moses foretold God would use to provoke Israel to jealousy and to anger. The question whether Israel knew answers itself, for Israel did know and had heard. Its failure to accept the gospel and Christ as Saviour came not from ignorance but from wilful refusal to believe, disobedience and resistance despite its privileges, stumbling over Christ.
God showed mercy to the Gentile nations by bringing them into the Christian fold and giving them the gospel and its blessings. What the gospel was doing for the world would thus come to Jewish ears and stir Israel to jealousy. Israel according to the flesh followed after the law of righteousness but did not attain it because it sought it not by faith but by works, while the Gentiles sought righteousness by faith and gained the precedence over them. This fulfills the sayings that the publicans and harlots go into the kingdom of God before the self-righteous and that the kingdom shall be taken away and given to a nation bringing forth its fruits.
God willed Israel to hold the most honorable place among the nations and to honor Israel even in calling the Gentiles. But Israel chose rebellion that brought the greatest dishonor, so the calling took place in a provoking manner instead of honoring Israel as it would have done had Israel received the gospel. Yet God did not cast Israel off for stumbling nor leave it to destruction, but endured it with much long-suffering and all day long stretched forth His hands to a disobedient and gainsaying people. With the result He was found of those who sought Him not and made manifest to those who asked not after Him.
The verse stands within the great argument of Romans 4 to 11 concerning man's sin, his utter need, and God's grace in saving him through Jesus Christ. It shows that the Lord makes no difference with His people, is no respecter of persons, and is rich unto all that call upon Him, whether Jew or Greek. Their sound went into all the earth and their words to the ends of the world, and even the heathen have heard through creation, as proved by the testimony that the heavens declare the glory of God and the firmament shows His handiwork. That light gives every intelligent person enough witness to be saved and responsible, so condemnation follows rejecting it, yet one ray of it is sufficient to save any soul who with all the heart lets it in.
In the first century the gospel had already gone into all the world, even to every creature under heaven. That worldwide preaching was the beginning of a still greater work of the same nature in the closing of the gospel dispensation to be carried forward with far greater power. It marks the first of two distinctly pointed-out special periods of gospel power and extent, given about twenty-eight years before the prophecy of Revelation 14 of the everlasting gospel preached to every nation, kindred, tongue, and people in connection with the hour of God's judgment at the second advent.