Against calumny there is no defense … having no helper, assistant nor shelter from the sword of accusation and the teeth of calumny, save God!
(‘Abdu’l-Bahá, Tablets of ‘Abdu’l-Bahá v2, p. 379)
And I say unto you that no calumny is able to prevail against the Light of God; it can only result in causing it to be more universally recognized.
(‘Abdu’l-Bahá, Paris Talks, p. 105)
The individual must be educated to such a high degree that he would rather have his throat cut than tell a lie, and would think it easier to be slashed with a sword or pierced with a spear than to utter calumny or be carried away by wrath.
(‘Abdu’l-Bahá, Selections from the Writings of ‘Abdu’l-Bahá, p. 136)