The Assistant Minister responsible for Culture has defended plans to spend £1.5 million promoting Jèrriais.
Deputy Montfort Tadier says the native language is part of what makes Jersey unique, and it should be protected to keep the island from becoming like a generic English town.
The money - set aside in the Government Plan - will be used over the next four years to teach the island's native language in schools and promote it through the Office du Jèrriais.
A proposition from St Saviour Deputy, Jeremy Maçon, was also passed - formally adopting the language on future government stationery and signage.
Deputy Tadier says the government needs to spend at least £375,000 to safeguard the future of the language, which would be a small fraction of what is currently being spent every year.