John 9:34

They answered and said unto him, Thou wast altogether born in sins, and dost thou teach us? And they cast him out.

The rage of the Pharisees is understandable. A publicly known beggar had defeated them with a syllogism which they could not answer and which was strongly believed by some of their own number (John 3:2). Far from defeating the blind man, they had only aroused him to a vigorous and skillful advocacy of his growing faith in Christ. He no longer said, "Whether he is a sinner, I know not," but now hurled the challenge in their faces, "If this man were not of God, he could do nothing? But, as is ever true, when error is defeated on the intellectual level, its proponents have recourse to slander, invective, and violence, never failing to employ any engine of coercion that might be available.

Born in sins ... This slander had already been refuted by Jesus (John 9:3), but they employed it anyway.

And they cast him out ... that is, out of the synagogue. Upon what grounds? If it must be spoken, upon grounds of spite. It was not upon the grounds of his confessing Christ, for he had not yet done that; but, as they saw his thinking moving in that direction, they cast him out for what they supposed that he would do, and not for what he had already done. His witness proved that Jesus was indeed the Messiah; and their drastic action against him was actually directed against the proof.