John Chrysostom — as excerpted in the Catena Aurea on John 9:8-17

“(Hom. lvii. 2) This they said, because they were meditating His death, having already begun to conspire against Him. Christ did not appear in company with those whom He cured; having no desire for glory, or display. He always withdrew, after healing any one; in order that no suspicion might attach to the miracle. His withdrawal proved the absence of all connexion between Him and the healed; and therefore that the latter did not publish a false cure out of favour to Him. He said, I know not.”