In Buddhism, particularly within the Mahayana tradition, reading the Heart Sutra (般若波羅蜜多心經) for those who have passed away is a common practice with various reasons:

• Transference of Merit: Buddhists believe in the concept of merit (功德), which refers to the positive energy generated through virtuous actions. By reading the Heart Sutra and dedicating the merit to the deceased, practitioners hope to transfer positive energy to help the departed soul in their journey beyond death.
• Aid in the Bardo State: In Tibetan Buddhism, there is a belief in the intermediate state or bardo (中有), which is the transitional phase between death and rebirth. Reading sacred texts like the Heart Sutra is thought to guide and benefit the deceased during this intermediate state, helping them to navigate the challenges and move towards a favorable rebirth.
• Wisdom and Liberation: The Heart Sutra emphasizes the concept of emptiness (空), the understanding that all phenomena lack inherent existence. Reading this sutra is seen as a way to share the wisdom of emptiness with the departed, facilitating their journey toward liberation from the cycle of birth and death (samsara).
• Cultivation of Compassion: The Heart Sutra also emphasizes compassion (悲), and reading it is considered an act of generating and expressing compassion for the deceased. It is a way to express care and concern for their well-being in their post-death journey.
• Connection to Bodhisattva Ideal: The Heart Sutra is associated with the bodhisattva Avalokiteshvara, who embodies compassion. By invoking Avalokiteshvara through the recitation of the Heart Sutra, Buddhists seek the compassionate blessings of this bodhisattva for the benefit of the departed.

Overall, reading the Heart Sutra for those who have passed away is a way for Buddhists to engage in spiritual practices that are believed to benefit the deceased, offer solace, and contribute to their spiritual well-being in the afterlife.