The readings of the texts here differ considerably, but without any essential difference of meaning. “Being convicted by their own conscience” is probably an addition made by some copyist to explain the meaning, which is quite clear without it.
Beginning at the eldest. — Literally, beginning at the elders; but our version gives the right sense, and prevents the possible mistake of understanding the word to mean the elders of the people. So “the last” should probably be taken, not of the lowest in official rank, but of the last who went out.
And Jesus was left alone, and the woman standing in the midst. — The scribes and Pharisees had probably stood close to Him. The woman was at some little distance, naturally shrinking from their gaze; but there is a crowd of people, including the disciples, around her, for they are in the Temple, and before this interruption He was engaged in teaching the people (John 8:2). Her accusers had “set her in the midst” (John 8:2), where she now stands. The whole scene is pictured with the minute detail of an eye-witness, who remembers how the persons were grouped, how the accusers went out one after another, and then, how Jesus was left alone, apart from the crowd, but that the others were still present.