Guiltlessness is invulnerability. Therefore, make your invulnerability manifest to everyone. Teach him that, whatever he may try to do to you, your perfect freedom from the belief that you can be harmed shows him that he is guiltless. He can do nothing that can hurt you, and by refusing to allow him to think he can, you teach him that the Atonement, which you have accepted for yourself, is also his. There is nothing to forgive. No one can hurt the Son of God. His guilt is wholly without cause, and being without cause, cannot exist.
Source: A Course in Miracles (Workbook for Students, Manual for Teachers)
Contributed by: WhoAmI