King James Version
Yea, so have I strived to preach the gospel, not where Christ was named, lest I should build upon another man's foundation:English Standard Version
and thus I make it my ambition to preach the gospel, not where Christ has already been named, lest I build on someone else's foundation,New International Version
It has always been my ambition to preach the gospel where Christ was not known, so that I would not be building on someone else's foundation.