And they began to enquire among themselves, which of them it was that should do this thing.
Matthew 26:22
And they were exceeding sorrowful, and began every one of them to say unto him, Lord, is it I?
Mark 14:19
And they began to be sorrowful, and to say unto him one by one, Is it I? and another said, Is it I?
John 13:22-25
22
Then the disciples looked one on another, doubting of whom he spake.
23
Now there was leaning on Jesus' bosom one of his disciples, whom Jesus loved.
24
Simon Peter therefore beckoned to him, that he should ask who it should be of whom he spake.
25
He then lying on Jesus' breast saith unto him, Lord, who is it?