All it means is that the government will not enter into your personal religious beliefs.
If only that was true. Several small religions, largely native American and Caribbean have religious rituals that involve controlled substances. Many are deined under federal law from practicing these rituals. The government banned important aspects of their religion. Religious freedoms are only free if they do not violate social norms. Only recently has peyote been made legal to use for some of these religions. So that's at least 50+ years of government denial of free religious practice.
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