predicto:

The Sermon was addressed to the Lost sheep of Israel, though.

You mean Jesus wasn't speaking to the Christians in Ephesus? Oh that's right, they didn't exist then. So who would you expect to find in Galilee at that time? Galileans? In saying, "Seeing the crowds, he went up on the mountain, and when he sat down his disciples came to him. And he opened his mouth and taught them", it's pretty safe to assume that the sermon has universal application.