Ver. 20,21. He gives a reason why he chose to preach the gospel in these places, because Christ had not been named or preached there before; this, he saith, was his ambition, and a thing that he greatly coveted; he was unwilling to
build upon another man’s foundation, to put his sickle into another’s harvest, to derive the glory to himself which would be due to others, 2Co_10:15,16. Again, another reason why he preached the gospel where Christ had not been named, was this, that so by him, as an apostle of Christ, and in his ministry, that scriptnre might be fulfilled, which you have in Isa_52:15, To whom he was not spoken of, they shall see, & c. See Poole on "Isa_52:15".