How and why was Murakami renamed in The Samurais tale?

In "A Samurai's Tale," Murakami is renamed Yoshi by Lord Daizen after he saves his life. This renaming is a sign of respect and honor, a way to acknowledge Murakami's bravery and loyalty. It also symbolizes Murakami's transformation from a lowly kitchen boy to a samurai warrior under Lord Daizen's tutelage.