Why Does the World-Honored One Not Expound the Profound Doctrine of Consciousness-Only to Ordinary Beings and Śrāvakas?

Original text of the Laṅkāvatāra Sūtra: 阿赖耶识甚深细，一切种子如瀑流。我于凡愚不开演，恐彼分别执为我。 

Explanation: The Ālayavijñāna is an extremely profound and subtle dharma, difficult to know, difficult to understand, and difficult to realize. The seeds contained within the Ālayavijñāna flow forth continuously like a rushing torrent, forming the various dharmas of the world of the five aggregates. This dharma principle—that the Ālayavijñāna flows forth seeds to produce worldly dharmas—I cannot expound for worldly ordinary beings and ignorant śrāvakas; if it were expounded, ordinary beings and śrāvakas would mistake the dharmas formed by the seeds for self and what belongs to self, and would again give rise to grasping (upādāna) toward them, thereby augmenting birth-and-death.

The dharmas of the five-aggregate world formed by the Ālayavijñāna through seeds are all contained within the five aggregates (pañca-skandha). The inner six elements and outer six elements, the six faculties and six consciousnesses, combine to form the eighteen dhātus, possessing the functions and activities of the five aggregates. The seeds inherently present within the Ālayavijñāna include the unborn-and-undying seeds of the seven great elements—earth, water, fire, wind, space, consciousness, and perception—while the externally entered seeds are the arising-and-ceasing karmic seeds left behind by the karmic actions of the five aggregates. These seeds combine and burst forth moment by moment, ceaselessly, like a rushing torrent, flowing forth without interruption year after year, month after month, day after day, kalpa after kalpa, causing the world of the five aggregates to arise and cease, transmigrating without stop. If such a profound and subtle dharma were expounded to ordinary beings and śrāvakas of the two vehicles, they would think that the dharmas of the five-aggregate world all originate from my Ālayavijñāna and all belong to what I possess—that since the Ālayavijñāna is not empty, I am not empty. This would cause them to grasp even more at the dharmas of the five-aggregate world produced by the Ālayavijñāna, and thus further increase birth-and-death.

But the bhūmi bodhisattvas who possess the seed-wisdom (种智) of Consciousness-Only have realized the functions and activities of all the seeds of the Ālayavijñāna, and have realized that the dharmas of the five-aggregate world are all illusorily manifested by the Ālayavijñāna through seeds—all are empty, with no real five-aggregate world. Therefore their wisdom no longer grasps at the world of the five aggregates; their minds become even more empty. They gradually transition from segmented birth-and-death (pariccheda-maraṇa) to the stage of transformational birth-and-death (parināma-maraṇa), tending toward great liberation and ultimate liberation. It can be seen that with the same dharma, because wisdom differs, cognitive understanding differs, and consequently practice also differs; the result is that one grasps even more, while the other has extinguished grasping and attained liberation.