Translation
And they began to question among themselves who then it might be of them who intending to do this.
Paraphrase
Then they began to debate among themselves about which one of them might be planning to, or ready to do such a thing.
And they began to question among themselves who then it might be of them who intending to do this.
Then they began to debate among themselves about which one of them might be planning to, or ready to do such a thing.