How is allusion used during Rev. Bsrbee's sermon in Invisible Man

Barbee is given the allusion to being Buddha-like, but what is most surprising to the narrator about his physical qualities is the shock that he is blind. Thus pretense is suggested; Barbee can orally illustrate a story for others but cannot see himself. He is hiding his blindness behind the glasses while creating an illusion for the audience to see into and believe.