John 13:26

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, &c.--Thus the sign of Judas' treachery was an affecting expression, and the last, of the Saviour's wounded love!

Our Saviour having finished his public discourses, in which he "endured the contradiction of sinners," now applies himself to a private conversation with his friends, in which he designed the consolation of saints. Henceforward we have an account of what passed between him and his disciples, who were to be entrusted with the affairs of his household, when he was gone into a far country; the necessary instructions and comforts he furnished them with. His hour being at hand, he applies himself to set his house in order. In this chapter I. He washes his disciples' feet (v. 1-17). II. He foretels who should betray him (Joh 13:18-30). III. He instructs them in the great doctrine of his own death, and the great duty of brotherly love (Joh 13:31-35). IV. He foretels Peter's denying him (Joh 13:36-38).

13:26 Meals included flat bread, which diners would dip into a common bowl. When Jesus gave a morsel to Judas (cp. Ruth 2:14), the disciples might have thought Jesus was honoring him. They did not understand what was occurring. They even thought that Judas’s departure (John 13:29) fulfilled an official duty for the feast! But Jesus was signaling to Judas that he understood Judas’s plan and was not taken by surprise. Jesus’ knowledge is profound and complete (see 1:48; 2:25).