Rabbi Chanina ben Dosa once preached a sermon on the rabbinic teaching "Receive every man as a friend" — every stranger, every wayfarer, every unknown face at your door. He finished his lecture, sent his students home, and walked out into the street.
There he came upon a hegemon, a high-ranking government official, apparently weary and unable to walk. Without asking questions, Chanina lifted the man onto his own shoulders and carried him through the city streets to Chanina's own house. He set the stranger down, washed his feet, prepared a full meal, and fed him. Then — because the stranger said he needed to return to his lodging — Chanina lifted him back onto his shoulders and carried him home.
When Chanina turned to leave, the stranger was gone. The sages in Heaven had sent an angel disguised as an official to test him — to see whether the Rabbi who preached kindness would practice it on a stranger who could return nothing, and indeed might be dangerous. Chanina had been found perfect: not only had he shown hospitality, he had shown it twice, without hesitation, on his own back.
Gaster's Exempla of the Rabbis (1924, No. 161) preserves this tale as a measurement of how closely a teacher's life matches his words. Chanina was famous for his miracles and his poverty. In this story, his greatness is simpler — a shoulder under a stranger's weight, and no questions asked until the stranger vanishes into light.