Repetition and emphasis are being used here to stress how the stereotype of the black male was feared and used as representative of evil. Atticus is using negative psychology to challenge the jurors to consider whether they are putting a racial stereotype on trial, or a real person-Tom Robinson. The fact that it takes the jury several hours to reach their decision rather than the expected few minutes. It shows that they heard what Atticus said, even if they did not have the courage to action it.
Atticus’ words are contentious. He uses the personal pronoun “our” when he refers to the women, reminding the jury that he is a white man like them, but sees deeper in to the implications of the trial before them.