The term "preacher of hate" can be seen as derogatory and could have legal implications. Therefore, there are alternative synonyms that can be used to convey the same meaning. One possible synonym is "inciter of violence," which suggests that the person in question actively encourages others to commit violent acts. Another option could be "proponent of intolerance," which captures the notion that the individual promotes a narrow-minded and discriminatory worldview. Finally, "spreader of extremist ideologies" can also be used to describe individuals who champion radical beliefs that reject fundamental human values. Overall, these synonyms allow for a more nuanced and accurate description of individuals who spread hateful and harmful messages.