How do we know that Simon and Matrena are kindhearted people?

In Leo Tolstoy’s story, Simon initially shows kindness and compassion when he decides not to turn away from the pale, naked man despite his initial fright. He then shows compassion again by giving the man a coat and boots. When he brings the stranger him into his home, his wife, Matryona, is initially annoyed because her husband had failed to complete all his errands, but she quickly realizes the man is in distress and invites him to eat with them. When she learns of her husband’s kindness in having clothed him, she extends this kindness by giving him more of Simon’s clothes. As the story continues, she support Simon’s decision to have the man—whom they learn is called Michael—stay with them and learn Simon’s trade of cobbler.
https://www.gutenberg.org/files/6157/6157-h/6157-h.htm