But he, desiring to justify himself, said to Jesus, “And who is my neighbor?” (Luke 10:29, ESV)
ὁ δὲ θέλων ⸀δικαιῶσαι ἑαυτὸν εἶπεν πρὸς τὸν Ἰησοῦν· καὶ τίς ἐστίν μου πλησίον; (Luke 10:29, NA28)
Charts made with Excel and Logos database.
The words πλησίον in the LXX translated.
The words translating רֵעַ in the LXX.
Neighbor can extend to friend and even countryman? It also means near. The Jews considered the Samaritan neither a friend or countryman, and he didn't live nearby. His journey did bring him near to the injured Jew in need. However, Jesus went way outside of who the man asking viewed as a neighbor. Jesus turn the question around from "Who is my neighbor?" to "Who is a neighbor?"
Most likely the two Jewish priests would have been worried about being defiled by a dead man:
Leviticus 21:1–4 concerns the family members for whom a priest may defile himself through corpse contact. These relatives include his mother, father, son, daughter, and brothers, each of whom is characterized as “his flesh, the one who is close to him [šĕʾērô haqqārōb ʾēlāyw].” His virgin sister, also described as “the one who is close to him [haqqĕrôbâʾēlāyw],” is included in this group because she has no husband. But his wife is explicitly excluded, and uncles, aunts, and cousins go unmentioned, suggesting their omission as well. Thus, according to Lev 21:1–4, the priest’s obligation to bury familial dead extends only to certain blood relations, whom we might characterize as his closest family members; it does not extend to the spouse, who is not a blood relation, nor to other family members, whom the text classifies implicitly as more distant by not including them among those characterized as “his flesh” and/or “close to him.” -- Olyan, S. M. (2017). Friendship in the Hebrew Bible. (J. J. Collins, Ed.) (p. 12). New Haven; London: Yale University Press.
This brings in a similar issue to Jesus' tension with the Jewish leaders over healing on the Sabbath.