Albert Barnes Commentary John 13:25

"He leaning back, as he was, on Jesus` breast saith unto him, Lord, who is it?" — John 13:25 (ASV)

He then lying on Jesus' breast. This is a different word from the one rendered John 13:23 leaning. It means falling back or laid his head back on the bosom of Jesus, so that he could speak to him privately without being heard by the others.