John Lightfoot on Luke 10:29

[And who is my neighbour?] This doubt and form of questioning he had learned out of the common school, where it is thus taught in Aruch. He excepts all Gentiles when he saith, His neighbour.

"An Israelite killing a stranger inhabitant, he doth not die for it by the Sanhedrim; because it is said, If any one lift up himself against his neighbour. And it is not necessary to say, He does not die upon the account of a Gentile: for they are not esteemed by them for their neighbour."

"The Gentiles, amongst whom and us there is no war, and so those that are keepers of sheep amongst the Israelites, and the like, we are not to contrive their death: but if they be in any danger of death, we are not bound to deliver them: e.g. If any of them fall into the sea, you shall not need to take him out: for it is said, Thou shalt not rise up against the blood of thy neighbour; but such a one is not thy neighbour."