Final answer:
Tom Robinson might use an allusion to compare his forgiveness to the Biblical story of Christ, and a metaphor likening his choice of forgivness to planting in a garden despite harsh soils, to express his forgiveness in a letter to Mayella Ewell.
Step-by-step explanation:
An allusion is a figure of speech that refers indirectly to a well-known story, event, person, or object in order to make a comparison in the readers' minds. For example, Tom Robinson could use an allusion to the Biblical story of Jesus Christ, who forgave those who wronged him, to convey his forgiveness to Mayella Ewell despite the pain her actions caused him. This could be represented in a phrase like 'Like Christ on the cross, I hold no ill will towards those who have trespassed against me.'
A metaphor, on the other hand, is a figure of speech in which a word or phrase is applied to an object or action to which it is not literally applicable. In a forgiveness letter, Tom might use a metaphor like 'In the garden of my life, where bitterness could easily take root, I instead choose to plant forgiveness, allowing it to bloom even in the harshest soils of injustice.'
The use of these literary devices is not only powerful in the context of a forgiveness letter but also reiterates the overall message of empathy, compassion, and understanding, which can be transformative for both the giver and receiver of forgiveness.