A tiny bit of compassion can have a huge impact.

Two weeks ago, Ehab Taha, a 26-year-old from Canada, was riding public transit in Metro Vancouver when a large man he described on Facebook as “suffering from drug abuse and\or mental health issues” became aggressive in his train car.

The man was alarming fellow passengers “with erratic movements, cursing, shouting” until a 70-year-old woman decided to reach out and help him by extending her hand and grabbing his.

Ehab Taha "At the end, he said 'Thanks, Grandma,' and walked away," Taha told HuffPost Canada.

The sweet gesture soothed the man. Eventually he sank to the floor of the train as tears flooded his eyes.

"It was quite incredible how much he calmed down in a split moment,” Taha told HuffPost Canada. “It was the most touching thing I've ever seen.”

Moved by “the incredible display of humanity,” Taha snapped a picture of the two holding hands and posted it to Facebook.

“I spoke to the woman after this incident and she simply said, ‘I'm a mother and he needed someone to touch.’ And she started to cry,” he wrote in the caption for the photo.

Although the woman felt a great amount of empathy for the man, like most, she was initially petrified to interfere.

"She was very brave,” Taha hold HuffPost Canada. “She even mentioned that she thought about what would happen if he stabbed her with the pen -- because he had one in his hand -- but she said it was more important he didn't feel alone."

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