Did not Israel know?

17 So then faith cometh by hearing, and hearing by the word of God. 18 But I say, Have they not heard? Yes verily, their sound went into all the earth, and their words unto the ends of the world. 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. 20 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. 21 But to Israel he saith, All day long I have stretched forth my hands unto a disobedient and gainsaying people. Romans 10:17-21