When a person passes away, their body undergoes certain physical changes, including the relaxation of muscles. The closing of the eyes is often due to the relaxation of the eye muscles, which can cause the eyelids to close. Similarly, the positioning of the hands across the stomach is a common practice in many cultures, often as part of the preparation of the body for burial or as a way to present the deceased in a respectful manner.
This positioning is often seen in traditional funeral practices, where the deceased might be laid out in a way that symbolizes peace and dignity. While it is not universally practiced, many cultures have rituals surrounding the treatment of the body after death that can influence how the deceased is positioned.
Ultimately, these practices serve both a practical purpose related to the physical state of the body and a cultural or symbolic purpose related to honoring the deceased.