大毘盧遮那成佛經疏 9.40

9.40

When the sūtra says: 'Then the Bhagavat further spoke the Dharmadhātu-origin Mantra': Previously, when the Bhagavat entered the Dharmadhātu-garbha samādhi, he saw that all sentient beings possess the bodhi-seed equal to all buddhas; hence he spoke the vidyādhara entering the Buddha's samaya. By means of this vidyādhara, one attains entry into the Buddha's equal precepts, which is the meaning of being deposited in the holy womb. At that time, the Bhagavat further contemplated all sentient beings with universal eyes, seeing that they were all fully endowed with the holy womb and born into the Buddha's family; at that time, their inexhaustible adornments were also equal to the Tathāgata's. Arising from this samādhi, he spoke the Dharmadhātu-origin Mantra. Again, contemplating with universal eyes, he saw that each and every one of these sentient beings fully accomplished vajra activities; at that time, their inexhaustible adornments were also equal to the Tathāgata's. Arising from this samādhi, he spoke the Vajrasattva Mantra. Therefore, these three are all called samaya. Furthermore, by entering the Buddha's samaya, one is not caused to perish prematurely in the womb. By the origin from the dharmadhātu, when first emerging from the womb one is free from all obstacles. By Vajrasattva, one is able to carry on the family heritage and master all arts. Furthermore, by entering the Buddha's samaya, one empowers the secret central womb; by the origin from the dharmadhātu, one empowers the two tiers of vajra and bodhisattva retinues; and by Vajrasattva, one empowers the various forms that conform to category. Entering the Buddha's samaya is like the lotus womb; the origin from the dharmadhātu is like the lotus blossom opening; and Vajrasattva is like the lotus bearing fruit and returning to become seed; therefore, these three are all called samaya.