Final answer:
Yes, state laws regulating religious speech and allowing it on Sunday only are permitted in certain cases, known as blue laws.
Step-by-step explanation:
Yes, a state law regulating the use of religious speech and allowing it on Sunday only is allowed in certain cases. These laws are known as blue laws and are religiously inspired regulations that limit working hours or even shutter businesses on Sunday. The courts have permitted these laws on the grounds that they help ensure the 'health, safety, recreation, and general well-being' of citizens, particularly on the Christian day of rest. However, it is important to note that the constitutional prohibition against laws respecting an establishment of religion means that the government cannot compose official prayers for religious programs.