Describe a person who often helps others

I'd like to talk about a neighbour of mine, whom everyone calls Uncle Sau. He's a retired electrician in his late sixties who lives at the end of our alley in Binh Thanh District in Saigon, and I've known him since my family moved there when I was six. He's the person the whole alley turns to when something breaks. Fans, rice cookers, a leaking tap, a motorbike that won't start: people simply carry the thing to his front step, where he sits with a toolbox and a glass of iced tea. He never takes money. If you insist, he waves his hand and says, "Pay me with a coffee," and then he usually forgets to collect it. During the lockdown in 2021, when hardly anyone was allowed out, he got a permit as a volunteer, and every few days he delivered vegetables and rice to about thirty households, hanging the bags on each gate. He also walks two elderly ladies to the health clinic every month, because their children work far away. I once asked him why he bothers, and his answer was quite simple. When he arrived in the city as a young man from Ben Tre, he had nothing, and a stranger let him sleep in a workshop for half a year and taught him the trade. He says he's still paying off that debt, just to different people. I suspect he's also the kind of man who gets restless if he isn't being useful. What I find remarkable is that he never makes anyone feel small for asking. Thanks to him, our alley feels more like a village than a corner of a huge city.