You assure me?
So the Holy Spirit taught about Jesus Christ to the Aztecs before the Spaniards ever got to Mexico? Why didn't the Spirit do that in the first place to ALL the world? Sorry, I disagree with you. The Spirit did not teach about Yahweh to the rest of the world. He wrote the "Law" (what Catholics call "natural law) on their hearts to recognize God - the nameless creator (to the Gentiles) of the World. To recognize that they should treat each other as they want to be treated - with love. This is the preliminary Gospel. But not the teachings of Jesus Christ, the way of the cross. That message only comes through the Apostles and those who had been sent by them.
Regards