Edmund Burke on Infidelity and Blind ZealIn The Early Life, Correspondence, and Writings of Edmund Burke, ed. Arthur Purefoy Irwin Samuels (Cambridge University Press), p. 176. Originally in the Reformer (April 7th, 1748).
The two greatest enemies of religion are infidelity and blind zeal, the former attacks it like an open enemy, and the latter, like an indiscreet friend, does it more harm than good. The first gives rise to the free thinkers, the latter to our sectaries. A truly religious life has the same efficacy to the prevention of both.