This chapter analyzes the fundamental transformation in religious freedom jurisprudence under Chief Justice John Roberts, documenting how the Supreme Court has systematically elevated Free Exercise Clause protections while weakening Establishment Clause constraints. Through statistical analysis and doctrinal examination, the chapter reveals an unprecedented shift from balanced church–state separation to preferential accommodation of religious claims, particularly those of mainstream Christianity. Statistical evidence demonstrates the magnitude of this transformation: the Roberts Court has ruled in favor of religious claims at an 83% rate compared to approximately 50% in previous eras. While the Warren Court exclusively protected religious minorities, the Roberts Court has favored mainstream Christian plaintiffs in seven out of nine cases, representing a fundamental shift in the constitutional purpose of religious freedom protections. The chapter examines key doctrinal shifts through landmark decisions. Trinity Lutheran v. Comer (2017) marked the watershed moment by requiring states to include religious institutions in public funding programs. Espinoza v. Montana Department of Revenue (2020) extended this logic to educational funding, while Carson v. Makin (2022) eliminated the distinction between religious status and religious use, effectively requiring states to fund religious instruction. Kennedy v. Bremerton School District (2022) culminated this transformation by abandoning the Lemon test and establishing history and tradition as the primary interpretive framework for Establishment Clause cases. The analysis reveals how the Court has eliminated the “play in the joints” principle, drastically constraining state and local government discretion in religious funding matters. Practical implications include mandatory taxpayer funding of religious activities, weakened protection for religious minorities, increased tension with anti-discrimination laws, and significant constraints on democratic governance and federalism principles. With the conservative supermajority firmly established, this transformation appears likely to continue and accelerate, fundamentally reshaping the relationship between government and religion in American constitutional law.