In Philip Roth's short story "The Conversion of the Jews," the Rabbi is described as making the following gesture:
Rabbi Binder was pointing one arm stiffly up at him; and at the end of that arm, one finger aimed menacingly. It was the attitude of a dictator, but one—the eyes confessed all—whose personal valet had spit neatly in his face.
These lines describe a dichotomy between public and private success or confidence. The Rabbi's gesture shows his power, which is absolute, like the power of a dictator. However, if you look into his eyes, you can see an expression that contradicts this display of power. Roth's way of expressing this is to imagine that, just before the dictator went out to address the cheering crowd, his manservant, who knows what he is really like, showed contempt and hatred by spitting at him. The knowledge that the person who is closest to him feels like this shows in his eyes, even when he is demonstrating his power.
This comment about the Rabbi is connected to the themes of the story, which are religious faith, and violence in the name of religion. The protagonist, Ozzie Freedman, questions the Rabbi's authority and religious knowledge, eventually forcing him to admit that his denial of Christ's divine origin is illogical. Rabbi Binder's immediate response, however, is to hit Ozzie on the nose for saying that he knows nothing about God. The power of the Rabbi is revealed as that of a small-minded, violent dictator rather than the authority of a wise spiritual counsellor and religious leader.