Samaritan

A person who selflessly helps others, especially those in distress. Taken from a parable in the Bible in which a Samaritan man was the only person who stopped to help a man who was robbed and beaten. Brad was hailed by the newspaper as a good Samaritan after he stepped in and helped a woman who was being robbed.

someone who tries to help people who have problems He's such a good Samaritan. He used to go shopping for my gran when she was ill.

A compassionate person who unselfishly helps others, as in In this neighborhood you can't count on a good Samaritan if you get in trouble. This expression alludes to Jesus's parable about a Samaritan who rescues and cares for a stranger who had been robbed and badly hurt and had been ignored by a priest and a Levite (Luke 10:30-35). The Samaritans were considered a heretical group by other Jews, so by using a Samaritan for the parable, Jesus chose a person whom his listeners would find least likely to be worthy of concern. [c. 1600]