The words profit, prophet sound the same but have different meanings and spellings. Why do profit, prophet sound the same even though they are completely different words?
The answer is simple: profit, prophet are homophones of the English language.
An advantageous gain or return; benefit.
The return received on a business undertaking after all operating expenses have been met.
The return received on an investment after all charges have been paid. Often used in the plural.
The rate of increase in the net worth of a business enterprise in a given accounting period.
A person who speaks by divine inspiration or as the interpreter through whom the will of a god is expressed.
A person gifted with profound moral insight and exceptional powers of expression.
A predictor; a soothsayer.
The chief spokesperson of a movement or cause.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.
If they are spelled the same then they are also homographs (and homonyms); if they are spelled differently then they are also heterographs (literally "different writing").