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"Upon" is a preposition which is often translated as "en", and "unto" is a preposition which is often translated as "a". Learn more about the difference between "upon" and "unto" below.
upon()
A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).
unto()
A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).