“Yea, so have I strived to preach the gospel, not where Christ was named, lest I should build upon another man's foundation:”
King James Version (KJV)
15:20 Not where Christ had been named - These places he generally declined, though not altogether, having an holy ambition (so the Greek word means) to make the first proclamation of the gospel in places where it was quite unheard of, in spite of all the difficulty and dangers that attended it. Lest I should only build upon another man's foundation - The providence of God seemed in a special manner, generally, to prevent this, though not entirely, lest the enemies of the apostle, who sought every occasion to set light by him, should have had room to say that he was behind other apostles, not being sufficient for planting of churches himself, but only for preaching where others had been already; or that he declined the more difficult part of the ministry
Ro 15:20 Yea, so have I strived to preach. He declares the fixed policy of his ministry not to preach where Christ had been heard, but in new fields. Where other apostles or evangelists had laid a foundation, he did not seek to build. Compare 2Co 10:12-16. As no apostle or great evangelist had yet visited Rome, his letter to the Romans was no violation of his principle.