Original quote from US Bill of Rights: "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof..."
Since government is by its very nature coercive, and religion is a deeply personal and private matter on which individuals differ greatly, there must be a complete separation of Church and State. No part of any government, nor any government funded organization or service, may do anything to either encourage or discourage religion in any way, either religion in general or any specific religion. This includes Atheism and Agnosticism, which are also religions. Freedom Of Religion includes Freedom From Religion. Government must have absolutely nothing to do with religion. References in the Declaration of Independence to the source of our rights were wisely made generic to avoid imposing a specific definition or interpretation of the word "Creator". No organized prayers or other religious activities may be held at any official government function or meeting (including in "public" schools if any) - those can be held privately by consenting individuals in otherwise unused rooms before or afterward, or individual silent prayers discreet enough to avoid disrupting the official function. No religious slogans or other religious material may be posted in government buildings, or on government property or official currency or coins, nor in government publications (except where it is the subject under discussion and the publication is clearly not promoting or discouraging religion or any religion), nor may religious displays or events occur on government property or be paid for in whole or in part by government funds. Government may not determine what is or is not a "valid" or "legitimate" religion or a religious belief, as that is strictly up to the individual believer.
An individual's inherent right to religious privacy applies against intrusions by not only government but other individuals and organizations as well. An individual's request to not be subjected to religious conversion, solicitation, or harassment must be respected, as must his right to refuse to reveal his own or anyone else's religious beliefs or affiliations. He may also require anyone that has information about his religious beliefs or affiliations to correct or delete such information, and reveal whomever such information has been provided to, upon request. Misrepresentation about someone's religious beliefs and motivations may be slander or libel.
Neither government nor any individual or organization may interfere with anyone's right to have and practice their religious beliefs, as long as they do not violate the Non-Aggression Principle. The only exception is as stated above; any conspicuous religious practice on government property, at government expense, or in a government context does violate NAP because it effectively creates a government-sponsored preference of the religion involved, and it also creates an atmosphere of intimidation against those of other beliefs. Both of these results violate the equal right of others to practice their own beliefs. Also, one cannot presume to have the right to conduct a conspicuous religious practice on or in someone else's property without their permission; for example, in a church of a significantly different religion. However, everyone has the inherent right to have their own beliefs, and to practice them on or in their own property, or inconspicuously (such as a silent prayer).
For the purposes of this section, "religion" also includes deeply held personal beliefs which are philosophical or political, as well as matters of marriage, sexual orientation, rules regarding sexual behavior (as long as NAP is not violated), and other such personal issues which are generally regarded as being influenced by religion. Government may not in any way discriminate on the basis of religious, political, sexual, or other philosophical beliefs or conduct, as long as NAP is not violated. Any allegation that someone's particular religious or sexual or political beliefs or practices constitute a threat to others or violate others' rights is subject to the same burden of proof as any such allegation not involving religion, sex, politics, etc. Marriage is a private matter between 2 or more consenting adult individuals of any race, religion, or sex; it is not the concern of government. The number, sexes, and sexual orientations of those in the marriage are strictly up to them and no one else may interfere without their consent. It is to be understood that the term "marriage" means different things to different people, and no one has the right to define it for anyone else.