Establishment Clause Freedom of Religion

In an 1802 letter President Thomas Jefferson wrote of a need to maintain a "wall of separation" between church and state so as to avoid unequal treatment of the young nation's citizens. The Establishment Clause of the Constitution has since become synonymous with the phrase "separation of church and state." The terms church and state have rather specific meanings in common usage. Church normally refers to a building used for public worship, particularly in the Christian religious tradition. The term church comes from the Greek word kuriakon meaning "of the Lord." The term state commonly refers to the 50 states composing the United States or similar political units in other countries. However, in constitutional law much broader meanings are involved for both. Church refers to any type or form of belief system, either organized religion or more personal beliefs. State refers to any collection of people politically organized under a single government.

Many cultures in the world do not clearly distinguish between the religious and non-religious aspects of their daily lives. However, peoples of Western Society, which primarily includes Europe and North America, commonly separate their religious life from everyday events. In addition to the distinction between religious and non-religious (secular), the United States has become an increasingly pluralistic society, characterized by the presence of multiple religious traditions. The use of Christian-associated materials and practices are often offensive to those who profess other religions, as well as to those who choose to practice no religion at all.

For many states, or governments, the church was envisioned as a principal means for maintaining social unity and suppressing unwanted ideas. However, the founders of the United States saw religion as a particularly divisive issue.