Bathroom box bugs

Religion in Real Estate Company: Boss Sending out Notices with Religious Phrases? - religious phrases

My boss tends to send letters to landlords and tenants, including asking them to pray for him or for others, religious or holiday event for our customers. Is this legal? We have) a real estate company (for rent. That scared me, I have often said that it might hurt others, but still ignored me. Where can I find laws that protect not only workers but also customers?