“Evil is no faceless stranger, living in a distant neighborhood. Evil has a wholesome, hometown face, with merry eyes and an open smile. Evil walks among us, wearing a mask which looks like all our faces.”

Source: The Invention of Wings

Unidentified fragment 651.

Attributed to Bonhoeffer on the Internet, and supposedly from Bonhoeffer: Pastor, Martyr, Prophet, Spy http://books.google.com/books?id=aG0q3X8TVpsC&pg=PA486#v=onepage (2010) by Eric Metaxas; however, there is no actual reference in that book. However, in advertising the book Metaxas does state on his site that the quote is from Bonhoeffer. http://ericmetaxas.com/books/bonhoeffer-pastor-martyr-prophet-spy/ First attributed to Bonhoeffer in Explorations 12:1 (1998), p. 3, as referenced by James Cone (2004) Theology's Great Sin: Silence in the Face of White Supremacy, Black Theology, 2:2, 139-152, footnote 1 http://dx.doi.org/10.1558/blth.2.2.139.36027
Compare "Not to Act, is to Act!" by Francis W. McPeek http://www.ergo-sum.net/pics/McPeek.jpg, The Missionary Herald at Home and Abroad, v.141-142 (1945-1946), "Missionary herald, 1945 - Congregational churches," pp.34-35 (We must realize that church inaction is a form of political action, and it is altogether negative. “Not to act, is to act.”)
Misattributed

Source: The Chronicles of Prydain (1964–1968), Book V : The High King (1968), Chapter 11 (p. 142)

Source: Mythology: Timeless Tales of Gods and Heroes

L'invidia, figliuol mio, se stessa macera,
E si dilegua come agnel per fascino.
Ecloga Octava; reported in Hoyt's New Cyclopedia Of Practical Quotations (1922), "Envy".

Part Troll (2004)

Source: The Financier (1912), Ch. XXVI