“...we should never think of separation except for repeated and enormous violations”

“Where we see the same faults followed regularly by the same misfortunes, we may reasonably think that if we could have known the first we might have avoided the others.”

“Besides the danger of a direct mixture of religion and civil government, there is an evil which ought to be guarded against in the indefinite accumulation of property from the capacity of holding it in perpetuity by ecclesiastical corporations. The establishment of the chaplainship in Congress is a palpable violation of equal rights as well as of Constitutional principles. The danger of silent accumulations and encroachments by ecclesiastical bodies has not sufficiently engaged attention in the U.S.”

“The purpose of separation of church and state is to keep forever from these shores the ceaseless strife that has soaked the soil of Europe in blood for centuries.[Letter objecting to the use of government land for churches, 1803]”

“Every new and successful example, therefore, of a perfect separation between the ecclesiastical and civil matters, is of importance; and I have no doubt that every new example will succeed, as every past one has done, in showing that religion and government will both exist in greater purity the less they are mixed together.”

“Those who are to conduct a war cannot in the nature of things, be proper or safe judges, whether a war ought to be commenced, continued, or concluded. Thy are barred from the latter functions by a great principle in free government, analogous to that which separates the sword from the purse, or the power of executing from the power of enacting laws.”

“Every new & successful example therefore of a perfect separation between ecclesiastical and civil matters, is of importance. And I have no doubt that every new example, will succeed, as every past one has done, in shewing that religion & Govt. will both exist in greater purity, the less they are mixed together.[Letter to Edward Livingston, 10 July 1822 - Writings 9:100--103]”