"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."
So, what does "establishment of religion" mean? Note also that this is specific to "Congress" that shall not make a law respecting and establishment of religion. And, what does "respecting" mean in context? "The First Amendment's Establishment Clause prohibits the government from making any law “respecting an establishment of religion.” This clause not only forbids the government from establishing an official religion, but also prohibits government actions that unduly favor one religion over another." Nowhere does it support atheists right to not believe in God or be bothered by anyone preaching the word of God. What it does is give you the right to exercise your belief in God that there is no God. But, it doesn't give atheists the right to make the government favor atheists over any religion or Church. Whether you want to admit it or not, your non-belief is a religious belief because you cannot prove that God does not exist any more than I can give you empirical evidence that he does exist.