It depends. Religious jokes or slurs, or offensive or obscene language intended to offend your religious beliefs, may be considered harassment, which courts have determined is a form of illegal discrimination. However, federal law does not prohibit simple teasing, offhand comments, or isolated incidents that are not extremely serious. The conduct must be sufficiently frequent or severe to create a hostile work environment or result in a tangible employment action, such as hiring, firing, promotion, or demotion.
Just like ssexual harassment, religious harassment may occur in the form of quid pro quo harassment or a hostile work environment.
Quid pro quo: This type of harassment occurs when a harasser seeks to exchange a tangible employment benefit, such as a promotion, for an individual's compliance with the harasser's religious demands, and when the demand is not complied with the harasser engages in an adverse employment action such as demotion or job loss.
Hostile Work Environment: This type of harassment occurs when there is offensive conduct directed at an employee due to that employee's religion, where the conduct is so severe or pervasive that it affects the terms or conditions of the employment and the employer fails to take reasonable steps to stop the conduct. Courts will look at the totality of the circumstances to determine whether or not a hostile work environment occurred.
Under the hostile work environment claim, an employer is liable if it knew or should have known religious harassment existed and failed to implement prompt action to stop the harassment. If a supervisor was the one creating the hostile work environment, the employer is liable. However, the employer may use a defense that the harassment resulted in firing, demotion, or any other tangible adverse employment action, and that the employer made an effort to quickly correct environment but the employee unreasonably failed to take advantage of any opportunities provided by the employer to correct the harm.