You can easily judge the character of a man by how he treats those who can do nothing for him. (Goethe)

And God takes notice of how we treat others.

"
The King will tell those on his right hand, ‘Come, blessed of my Father, inherit the Kingdom prepared for you from the foundation of the world; for I was hungry, and you gave me food to eat. I was thirsty, and you gave me drink. I was a stranger, and you took me in. I was naked, and you clothed me. I was sick, and you visited me. I was in prison, and you came to me.’

Then the righteous will answer him, saying, ‘Lord, when did we see you hungry, and feed you; or thirsty, and give you a drink? When did we see you as a stranger, and take you in; or naked, and clothe you? When did we see you sick, or in prison, and come to you?’

The King will answer them, ‘Most certainly I tell you, because you did it to one of the least of these my brothers, you did it to me.’
"
(Matthew 25.34-40 WEBBE)

_

Related: Unto strangers