John 13:11

11 For he knew who was going to betray him, and that was why he said not every one was clean.

Read John 13:11 Using Other Translations

For he knew who should betray him; therefore said he, Ye are not all clean.
For he knew who was to betray him; that was why he said, "Not all of you are clean."
For Jesus knew who would betray him. That is what he meant when he said, “Not all of you are clean.”