[Sarah] Grimké's contribution to antislavery agitation was pivotal, not only because of her considerable talent as a writer, speaker, teacher, and pamphleteer, but also because of her sex, southern nativity, and uncommon courage. As leaders of the female antislavery movement, Sarah and Angelina regularly risked physical harm and slander. They were the only women to brave social custom and charges of "heresy" in the 1837 speaking tour of New England; with Abigail Kelley, Frances Wright, Maria Stewart, and several others, Sarah made it possible for later generations of women to occupy public spaces without fear (as happened on one occasion) of having to run a gauntlet of jeering men and boys. Sarah's elegant mapping of similarities (and, occasionally, of differences) between white women in America and African-American slaves--and especially her insistence that white women learn to empathize more completely with black women--elevated her to the first rank of social reformers and Christian-feminist theoreticians. As historian Larry Ceplair put it, Sarah Grimké and her devoted sister were genuine "revolutionaries" in a land not given to revolutionary change, "increasingly conscious that they were blazing a public path for women of courage who had seen a light or heard a voice of truth" (Ceplair, p. xi).
Mary Jo Miles, "Grimké, Sarah Moore," American National Biography Online, February 2000, http://www.anb.org/articles/15/15-00294.html.