In language revitalisation movements the main impetus and passion is often provided by adults who, as second language speakers, have gained fluency in their heritage language. As parents and teachers these adults often have vital roles in the ongoing transmission of the heritage language. This study is based on interviews with thirty-two Māori adults who have each made a strong commitment to becoming a fluent speaker of Māori. The study posited that the informants would have a strongly-held worldview which enabled them to engage with and maintain a relationship with the Māori language. This worldview is expressed through a range of metaphors, the four most frequent being: LANGUAGE IS A PATH, LANGUAGE IS A CANOE, LANGUAGE IS FOOD, LANGUAGE LEARNER IS A PLANT. The worldview articulated by these metaphors has a quasi-religious nature and draws on elements of New Age humanism, a connection with Māori culture and ancestors as well as kaupapa Māori (Māori-orientated and controlled initiatives). The source domains for these metaphors are traced through a study of various Māori sources from the 19th century through to the present day. This study shows how exploitation of these metaphors has changed throughout this time period leading to their current exploitation by the newly-fluent informants. The metaphors preferred by the informants were contrasted with the prominent metaphor LANGUAGE IS A TREASURE, the entailments of which were found to be more relevant to the experience of native speakers. The informants' experience also contrasts with the focus of language planners in that the informants are more focussed on how the Māori language is important for them personally than how they contribute to the revitalisation of the Māori language. These findings have implications for the revitalisation of the Māori language and have relevance for other endangered languages.