>>24504014 (OP)The ancient Aryan Bhagavad Gita is about a chariot driver convincing the warrior he drives to have no fear for the coming battle they’re staring down. The elimination of fear by teachings of the immortal soul is a fairly central part of it.
Not what you’re looking for, but the Germanic cosmic cycle is also centred around the death and rebirth of the deity Baldr, meaning boldness, or fearlessness, from whom the wisest peace-bringing judgement of the world is said to derive. This is described in Gylfaginning and the poem Voluspa. The Volsung Saga also discusses the death and rebirth of a family tradition of fearlessness, in a way that reflects the cosmic cycle on earth, which thereby acts as a bridge to make the myths of the gods more relatable to the lives of man. Scholars like Dumezil connect characters like Baldr to the same poem the Bhagavad Gita is from, which is a more philosophical text like what you’re looking for.