How are congressional chaplains legal despite the establishment clause state?

Congressional chaplains are considered legal under the Establishment Clause because they serve a ceremonial role rather than promoting a specific religion. The Supreme Court has upheld the practice, viewing it as a tradition that acknowledges the historical role of religion in American public life without endorsing or establishing a state religion. Additionally, the presence of chaplains is seen as providing a service for lawmakers, fostering a sense of unity and moral guidance rather than coercion.