
"The Lesson of Emancipation to the New York Generation: An Address Delivered in Elmira, New York" (3 August 1880), as quoted in The Frederick Douglass Papers http://tfdf.org/blog/2012/05/15/why-i-am-a-republican-by-dr-james-taylor/, Volume 4, p. 581. Douglass is referring to Psalm 137:5-6.
1880s, The Lesson of Emancipation to the New York Generation (1880)