Excerpts from Books and Wikipedia
"At first, preacher Lyman Beecher thought it was a dark day; but later he recalled, "'It cut the churches loose from dependence on state support. It threw them wholly on their own resources and on God.' . . . The Bill of Rights, added to the national Constitution in 1791, read: 'Congress shall make no law respecting an establishment of religion or prohibiting the free exercise thereof." Applying specifically to Congress, this First Amendment restricted the federal government only, not the states. . . . Under Republican leadership, New Hampshire separated church from state in 1817, and Connecticut in 1818, leaving Massachusetts the only state with an establishment of religion, which would endure until 1833. . . . Now, the Americans undertook to experiment with their separation: Religion would be purely voluntary. The results astonished both friends and foes of Christianity. 'They say ministers have lost their influence; the fact is, they have gained' by disestablishment, Beecher observed. Far from hindering religion, the American model of voluntarism hugely facilitated it, liberating powerful religious energies."