<< clearly states the seperation between church and state >>
Well, it states something, but it doesn't 'clearly state the separation between church and state'. That is simply how its been interpreted.
What it does state is "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof;" The prohibition was originally on Congress (a legislative body), which was then applied to the state legislative bodies via the 14th Amendment. Though, that still doesn't dispense with the prohibitive language "make no law". If I hang the 10 Commandments in my 4th grade elementary public school, have I "made law" (just an example, I'm not a teacher)? Only in the most expansively permissive figurative terms possible.
The constitution states something, but stating it clearly it does not (unless the current interpretation is flat wrong, then the amendment becomes very clear).