Answer:
The First Amendment
Step-by-step explanation:
The first Amendment states "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." This doesn't express an aggressive separation of church and state, but rather a complete neutrality toward religion (and religious rights to practice).