John 13:26

26.To whom I shall give the dipped sop. It may be asked, what purpose did it serve to give a dipped sop, for discovering the traitor, when Christ might have openly pointed him out by name, if he wished to make him known? I answer, the sign was of such a nature, that it discovered Judas to one person only, and did not immediately bring him forward to the view of all. But it was advantageous that John should be witness of this fact, in order that he might afterwards reveal it to others at the proper time; and Christ intentionally delayed to make Judas publicly known, that, when hypocrites are concealed, we may more patiently bear, till they are dragged forth to the light. We see Judas sitting amongst the others, and yet condemned by the mouth of the Judge. In no respect better is the condition of those who hold a place among the children of God.