Jamieson, Fausset and Brown on Romans 10:20

20. But Esaias is very bold, and saith--that is, is still plainer, and goes even the length of saying.

I was found of them that sought me not--until I sought them.

I was made--"became"

manifest unto them that asked not after me--until the invitation from Me came to them. That the calling of the Gentiles was meant by these words of the prophet (Is 65:1) is manifest from what immediately follows, "I said, Behold Me, behold Me, unto a nation that was not called by My name."