According to the narrative, what makes dying in front of a saint an act of 'great merit'?

Chapter 31 explains that leaving the body before a saint's eyes is an act of great merit because it ensures the soul's redemption and liberation. The text posits that for any creature, this act saves it from all its sins (verse 143). It is considered an extraordinary deed of destiny, suggesting that a debt from a past life is paid, and the soul becomes debt-free (verse 144). This event is not something that happens by chance; the scripture states that it requires "great fortune" for a body to fall before a saint's eyes and for its liberation to occur. It is the ultimate "earning of life," leading to a state where there is no rebirth for that soul.