Final answer:
The Supreme Court decision in question is Abington School District v. Schempp, which deemed mandatory Bible reading in public schools unconstitutional as per the Establishment Clause of the First Amendment, reinforcing the separation of church and state.
Step-by-step explanation:
The Supreme Court decision that held a Pennsylvania law requiring Bible reading in schools as unconstitutional is Abington School District v. Schempp. This landmark 1963 decision is significant for affirming the separation of church and state by highlighting the Establishment Clause of the First Amendment, which prohibits the government from establishing an official religion or unduly favoring one religion over another.
The Engel v. Vitale case reinforced this by ruling that state officials cannot compose an official school prayer and require its recitation. The First Amendment ensures protection for free expression and religious freedom, which has been championed as necessary for a robust and open discussion, especially when it involves controversial or unpopular views.
Subsequent court decisions, including cases like Locke v. Davey and those involving the Religious Freedom Restoration Act (RFRA), continue to navigate the complex relationship between the free exercise of religion and governmental policies, affecting the interpretation of the First Amendment. These interpretations and rulings emphasize the importance of both preventing government entanglement in religious affairs and protecting individual religious freedoms.