Romans 15:19-20

with the power of signs and wonders, [and all of it] in the power of the Spirit. So [starting] from Jerusalem and as far away as Illyricum, I have fully preached the gospel [faithfully preaching the good news] of Christ [where it had not before been preached]. Accordingly I set a goal to preach the gospel, not where Christ’s name was already known, so that I would not build on another man’s foundation