Judas was last mentioned in verse 14; here he is identified as the one who betrayed him, which may be translated “the one who had agreed to turn Jesus over to his enemies.”

Is it I, Master? is word-for-word the same question in Greek as that of the rest of the disciples (verse 22), except that Judas substitutes Master (Good News Translation “Teacher”) as a noun of address for “Lord.” Master (RSV footnote “Rabbi”) is discussed at 23.7. In many languages this noun of address must precede the question.

You have said so (Good News Translation “So you say”) translates an expression which, dependent upon the context, may be understood as either a denial or an affirmation. The majority of scholars apparently interpret Jesus’ reply to be in agreement with Judas’ question: “You have said so, and what you say is true.” Barclay has “You have said it yourself!” The Good News Translation question and response do not relate clearly to each other and do not make the best model.

Quoted with permission from Newman, Barclay M. and Stine, Philip C. A Handbook on the Gospel of Matthew. (UBS Handbook Series). New York: UBS, 1988. For this and other handbooks for translators see here .