First Amendment:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
The Free Exercise Clause . . . withdraws from legislative power, state and federal, the exertion of any restraint on the free exercise of religion. Its purpose is to secure religious liberty in the individual by prohibiting any invasions there by civil authority.
1 It bars governmental regulation of religious beliefs as such,
2 prohibiting misuse of secular governmental programs to impede the observance of one or all religions or . . . to discriminate invidiously between religions . . . even though the burden may be characterized as being only indirect.
3 Freedom of conscience is the basis of the Free Exercise Clause, and government may not penalize or discriminate against an individual or a group of individuals because of their religious views nor may it compel persons to affirm any particular beliefs.4 Interpretation is complicated, however, by the fact that exercise of religion usually entails ritual or other practices that constitute conduct
rather than pure belief.
When it comes to protecting conduct as free exercise, the Court has been inconsistent.5 It has long been held that the Free Exercise Clause does not necessarily prevent the government from requiring the doing of some act or forbidding the doing of some act merely because religious beliefs underlie the conduct in question.6 What has changed over the years is the Court’s willingness to hold that some religiously motivated conduct is protected from generally applicable prohibitions.