From the very beginning of His ministry. And Jesus said, "In this gospel of the kingdom, the one He had been preaching, will be preached in all the world as a witness to all the nations, and then the end will come." There are not two gospels, one preached by Jesus and another preached by Paul or by Luther. So Jesus is always our supreme teacher. If we are interpreting the apostles in a way that contradicts Jesus, then we are misinterpreting the apostles.