Fannie Lou Hamer and Thomas Merton were both, as Albert Raboteau puts it, religious radicals. Hamer became an outspoken advocate for racial and social justice; she risked her life to secure voting rights and political equality for African Americans. Thomas Merton was a Catholic contemplative who spoke out forcefully against racism, militarism, and rampant consumerism.
Albert Raboteau, American Prophets: Seven Religious Radicals and Their Struggle for Social and Political Justice Princeton University Press, 2016