>>17905123
>by neighbor, he ment your fellow Jew.
This is an easy assumption to make, but Taking for granted the typical academic idea that Mark was the first gospel, and then noting that Matthew has in some cases apparently modified Mark's stories to be less gentile-friendly, (e.g. intensfying the story of Jesus meeting the gentile woman who accepts being called a dog by having Jesus say "I came only to the lost sheep of the house of Israel" and conspicuously removing the "for all nations" part of Jesus quoting "My house will be called a house of prayer for all nations" from Isaiah.) I actually think it's possible that there was a very early even more gentile-friendly narrative that got edited for being too scandalous before the direction of bias reversed as Christianity got mostly out of the Jews' hands and into gentile hands.
Even in the Tanakh there are many passages that could be used to argue for loving more than just fellow Jews, like Deuteronomy 10:19, "And you are to love those who are foreigners, for you yourselves were foreigners in Egypt."
Also I think Bart Ehrman believes the historical Jesus had a very universal understanding of how altruism should be applied, though I'm not sure how he argues for it.