No. In Connecticut there is a statute, Conn. Gen. Stat. § 53-303e, which says that your employer may not make you work more than six days in any calendar week. Furthermore, your employer may not terminate you if you refuse to work all seven days. Any such claim may not be brought in court, but instead in the Connecticut Department of Labor.
Can my employer fire me for refusing to work seven days a week?
This statute also includes a section saying that an employee’s refusal to work on his Sabbath cannot constitute grounds for dismissal. This portion of the statute is no longer good law since it was ruled to be an unconstitutional violation of the separation of church and state.
The rule of this law is, that while an employer MAY NOT fire you for complaining about working seven days per calendar week, your employer MAY fire you for refusing to work on your Sabbath.