How Does the Ālayavijñāna Migrate from Body to Body?

Original text: 贤护白佛言。世尊。众生虽知有识。如宝闭在箧中。不显不知。世尊。不知此识。作何形状。何故名识。众生死时。手足乱动。眼色变异。制不自由。诸根丧灭。诸大乖离。识迁于身。去至何所。自性如何。作何色相。云何舍离此身。更受余身。

Explanation: Bhadrapāla said to the Buddha: "World-Honored One, although sentient beings know that they possess the Ālayavijñāna, it is like a jewel locked inside a box—it cannot manifest, and they themselves do not know it. World-Honored One, we do not know what shape this mind consciousness takes, or on what account it is named 'consciousness.' When sentient beings die, their hands and feet flail about, the expression in their eyes changes, and they gradually lose control of themselves. The faculties gradually perish, the four great elements separate from one another, and the Ālayavijñāna then leaves the material body—where does He go? What is the self-nature of the Ālayavijñāna like? Does He have any form or appearance? Why does He leave this material body and then take up another material body?"

There are two kinds of understanding among Buddhist practitioners regarding this consciousness: one kind knows only that there are the six consciousnesses and the mind consciousness; the other kind, besides knowing there are the six consciousnesses, also knows there is an Ālayavijñāna. Of these two—the mind consciousness and the Ālayavijñāna—which one is the jewel described here? Because the six consciousnesses cannot manifest all dharmas, the six consciousnesses are not the maṇi jewel; the jewel that can be called the maṇi jewel refers to the Ālayavijñāna, which gives rise to the myriad dharmas. The Ālayavijñāna is like a jewel locked inside a box, and this box refers to the five-aggregate body. Because He is hidden within the five-aggregate body, this jewel is not discovered by sentient beings. In fact, this jewel is constantly radiating brilliant light; it is only that sentient beings themselves do not know it. It is not that the jewel does not manifest, but rather that sentient beings' minds are obscured by the five aggregates—it is because sentient beings' minds have ignorance that creates obstruction that they cannot see this treasure within their own bodies. He has always been radiating brilliant light within sentient beings' five-aggregate bodies, illuminating everything; it is only that, because sentient beings have ignorance, the Ālayavijñāna remains hidden within the five-aggregate body and is not discovered. In fact, the jewel itself has never been locked away.

Bhadrapāla Bodhisattva asks what the form and appearance of the Ālayavijñāna is: does this consciousness have a shape? Does it have length or shortness, squareness or roundness, size, or color? Is it like the six sense objects of worldly dharmas—having sound, color, form-appearance, scent, taste, touch, or mental objects? What is His appearance and characteristics, and why is He called the Ālayavijñāna? When sentient beings die, the Ālayavijñāna certainly must separate from the body. But some sentient beings, at the time of death, suffer so much that their hands and feet flail about—these are sentient beings who have created unwholesome karma. Their appearance at death is rather unsightly, and their dying is rather painful; because of the pain, their hands and feet flail and struggle incessantly.