Final answer:
Frederick Douglass delineates the contrast between the Christianity practiced by American slaveholders and the true teachings of Christ, asserting that the former is corrupt and in direct conflict with Christian ethics.
Step-by-step explanation:
Frederick Douglass's statement "between the Christianity of this land and the Christianity of Christ, I recognize the widest possible difference" highlights his view that the Christianity practiced in America, especially as it relates to slaveholders, is fundamentally at odds with the teachings of Christ. These were supposed to be about love, compassion and equality. Douglass feels compelled to add this clarification because he does not want to be misunderstood as being against Christianity in general but rather against the hypocritical version of it that justifies and perpetuates slavery.
In support of his claim, he provides evidence of the stark contrast between the claimed Christian values and the actual behaviors of those involved in slavery. He notes that slaveholders, who are also church members, ministers, and missionaries, enact violence and theft against slaves—practices that are in direct conflict with Christian doctrine. Consequently, Douglass seeks to delineate the profound gap between the pure, ethical teachings of Christ and the corrupt, self-serving distortion of those teachings by people who perpetuate slavery.