It was only after Israel rejected the Messiah for the final time by stoning Stephen, then Jesus's death on the cross meant something to the entire world.
We now understand that because we were born in this time period.
But as far as one who is born listening to Jesus in John 10, he would only think he died for Israel and the Jews only. That was what Satan thought too during Jesus first coming, that was why he was more than willing to ensure Jesus's death on the cross.
But he realized, too late, that Jesus death was not only for Israel, but it also allowed God to reconcile with the entire world of gentiles, thru the fall of Israel. That is the mystery revealed to Paul.
Read Romans 9-11 for all the details you need.