To be a Good Samaritan means to be helpful to another person in need, with no talk or expectation of getting a reward in return. This is a Biblical reference.
Note: both 'Good' and 'Samaritan' begin with a capital letter.
1. When the earthquake left numerous people homeless, the college Principal became a Good Samaritan and gave some people shelter on the large campus grounds.
2. Shyamala was always a Good Samaritan whenever a fund-raising event had to be organized.
3. The billionaire led an opulent lifestyle but donated huge amounts to charity and was a Good Samaritan in volunteering to help out at the orphanage.