Jamieson, Fausset and Brown on Luke 10:33

33. Samaritan--one excommunicated by the Jews, a byword among them, synonymous with heretic and devil (Joh 8:48; see on Lu 17:18).

had compassion--His best is mentioned first; for "He who gives outward things gives something external to himself, but he who imparts compassion and tears gives him something from his very self" [Gregory The Great, in Trench]. No doubt the priest and Levite had their excuses--It is not safe to be lingering here; besides, he's past recovery; and then, may not suspicion rest upon ourselves? So might the Samaritan have reasoned, but did not [Trench]. Nor did he say, He's a Jew, who would have had no dealings with me (Joh 4:9), and why should I with him?