These twelve Jesus sent out, charging them, "Go nowhere among the Gentiles, and enter no town of the Samaritans, but go rather to the lost sheep of the house of Israel. And preach as you go, saying, `The kingdom of heaven is at hand.'

Matthew 10:5-7

“But what is also to the point, let us note that the very tradition, teaching and faith of the Catholic Church from the beginning was preached by the Apostles and preserved by the Fathers. On this the Church was founded – and if anyone departs from this, he neither is, nor any longer ought to be called, a Christian.”

- St. Athanasius