Upon my arrival in the United States, the religious aspect of the country was the first thing that struck my attention; and the longer I stayed there, the more did I perceive the great political consequences resulting from this state of things, to which I was unaccustomed. In France I had almost always see the spirit of religion and the spirit of freedom pursuing courses diametrically opposed to each other; but in America I found that they were intimately united, and that they reigned in common over the same country. My desire to discover the causes of this phenomenon increased from day to day. In order to satisfy it, I questioned the members of all the different sects; and I more especially sought the society of the clergy, who are the depositories of the different persuasions, and who are more especially interested in their duration. […] they mainly attributed the peaceful dominion of religion in their country, to the separation of Church and State. I do not hesitate to affirm that during my stay in America, I did not meet with a single individual, of the clergy or of the laity, who was not of the same opinion upon this point.
This led me to examine more attentively that I had hitherto done, the station which the American clergy occupy in political society. I learned with surprise that they filled no public appointments; not one of them is to be met with in the administration, and they are not even represented in the legislative assemblies. In several States the law excludes them from political life; public opinion in all. And when I came to inquire into the prevailing spirit of the clergy, I found that most of its members seems to retire of their own accord from the exercise of power, and that they made it the pride of their profession to abstain from politics.
[…] I learned from their discourses that men are not guilty in the eye of God for any opinions concerning political government, which they may profess with sincerity, any more than they are for their mistakes in building a house or driving a furrow.
Democracy in America – Volume 1 – 1835
by Alexis de Tocqueville