In Jainism, the concept of "best friend" is not defined in terms of personal relationships as in modern social contexts. Instead, Jain teachings emphasize friendship (maitrī) towards all living beings. One of the central vows for laypersons (śrāvakās) and ascetics is to cultivate universal friendship, compassion, and equanimity.

The prayer of universal friendship (Maitrī Bhāvanā) is an important part of Jain spiritual practice, where one wishes well for all living beings: "May all beings be happy, may all beings be free from fear, may all beings attain peace."

Therefore, according to Jain philosophy, the best friend is one who helps you progress on the path of right faith, right knowledge, and right conduct (Samyak Darshan, Samyak Jnana, Samyak Charitra). In this sense, your best friend is anyone who inspires you to follow the path of non-violence (ahimsa), truth (satya), and spiritual upliftment.

If you are asking about a specific person named "Jain," please clarify your question. If you are asking in the context of Jainism, then the concept of universal friendship applies.