December 21

How grievous it is to see how man has used his God-given gift [of understanding or intellect] to frame instruments of war, for breaking the Commandment of God ‘Thou shalt not kill’, and for defying Christ’s injunction to ‘Love one another’.

God gave this power to man that it might be used for the advancement of civilization, for the good of humanity, to increase love and concord and peace. But man prefers to use this gift to destroy instead of to build, for injustice and oppression, for hatred and discord and devastation, for the destruction of his fellow-creatures, whom Christ has commanded that he should love as himself!

I hope that you will use your understanding to promote the unity and tranquillity of mankind, to give enlightenment and civilization to the people, to produce love in all around you, and to bring about the universal peace. 
(‘Abdu’l-Baha, from a talk, Paris, October 26, 1911, ‘Paris Talks’)