Matthew 26:22
"And they were exceeding sorrowful, and began every one of them to say unto him, Lord, is it I?"
Cross References (ranked by relevance)
Luke 22:23
And they began to enquire among themselves, which of them it was that should do this thing.
John 21:17
He saith unto him the third time, Simon, son of Jonas, lovest thou me? Peter was grieved because he said unto him the third time, Lovest thou me? And he said unto him, Lord, thou knowest all things; thou knowest that I love thee. Jesus saith unto him, Feed my sheep.