Jesus answered - also inaudibly, the answer being communicated to Peter perhaps from behind.
He ... to whom I shall give a sop when I have dipped it - a piece of the bread soaked in the wine or the sauce of the dish; one of the ancient ways of testifying peculiar regard; compare Joh 13:18, “he that eateth bread with Me.”
And when he had dipped ... he gave it to Judas, etc. - Thus the sign of Judas’ treachery was an affecting expression, and the last, of the Savior's wounded love!