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.
If you truly wish to understand the First Amendment, you would be wise to study/read the Federalist Papers, writings of the individual founding fathers, and the Debates on the Constitution, and of course the letters sent by each of the founders to others (even though this may be considered part of their writings, I view them as personal correspondence.)
There is a wide array of information, books, web-sites, articles, etc. concerning the founders and their intention. Me personally, I am both an Originalist and a Textualist…I believe the Constitution and the Bill of Rights live on with the original meaning that the founder’s intended and can be used in all governmental circumstances; also, I believe the founders wrote exactly what their intentions were in word form and can be gleaned from the text we presently have before us. I do not believe it to be a “living document” that is breathed new meaning with the advent of a new generation. You may not like the right that someone has, but guess what…not everyone likes the rights you are exercising!
“I do not agree with what you have to say, but I’ll defend to the death your right to say it.” ~Voltaire