There are numerous synonyms for the phrase "by God/gum/Jove etc." which are generally used to add emphasis to a statement or to express surprise or excitement. Some of the most common synonyms include "by golly," "for crying out loud," "good heavens," "by Jove," "by George," "by thunder," "by gum," "by Jiminy," and "by Zeus." Each of these expressions has its own unique origin and connotation, but all serve the same purpose of adding emphasis, and can be used interchangeably in most contexts. Whether you're expressing shock, frustration, or enthusiasm, these synonyms are useful additions to your vocabulary.