The Buddha Shakyamuni instructed us to share the Dharma in the language of each community. While it is appropriate for ethnic groups from traditionally Buddhist countries to come together and share the Dharma in their own languages, it is the duty of the ordained Sangha to make the teachings and practices available to all in the area in which they reside.
The Buddha spoke Magadhi, and not Pali, Sanskrit, Chinese, Tibetan, Japanese, Thai, or any other language that we understand today.
All that we know of the Dharma has reached us in translation. Without the translation efforts of the great Tripitaka Masters, we would not have the any of the teachings.
Giving any language a ‘sacred’ status, no matter how old or beautiful, is contrary to the Dharma. The purpose of language is communication, and that is always best achieved in the vernacular.