Rabbi Jose said: 'I was perplexed by the verse "V'hayisa m'mashesh b'tzaharayim ca'asher y'mashesh ha'eevair ba'afelah." (You shall be perplexed at noon as the blind grope in the darkness).
Why does it say that the blind grope in the darkness? What difference does it make to a blind man whether it is dark or light?
The answer came to me after many years when I came upon a blind man carrying a torch on a pitch black night. He told me that as long as he has the torch in his hand people see him and save him from holes, thorns and briars.'
Talmud Tractate Megilla pg. 24b
In this story, the blind man was lighting up the way for other people, yet he was benefitting from the light because others saw the light that he provided. Torah is compared to light. By providing others with Torah, one is surrounded by light.
As a result, because others helped him, the blind man's body was not destroyed by thorns and pitfalls. It is interesting that the author of this saying, Rabbi Yose, is the one who wrote, "Whoever honors the Torah, his body is honored by people. Whoever disgraces the Torah, his body is disgraced by people. (Ethics of the Fathers 4:8).