大毘盧遮那經阿闍梨真實智品中阿闍梨住阿字觀門 1.14

1.14

所以經云：「迦、左、吒、哆、跛初中後相，加以等持品類相入，自然獲得菩提心行，成等正覺及般涅槃。」即是初阿、阿、暗、噁四重之義；又迦、左、吒、哆、跢等二十字，即是中義；其伊、伊至污、奧凡十二字，即是加以等持品類之義；又仰、壤、拏、曩、莽至[唬-儿+(雪-雨)]、弱、搦、諾、莫等二十字，即是後相義。

Therefore the sūtra states: 'The beginning, middle, and end aspects of *ka*, *ca*, *ṭa*, *ta*, and *pa*, added with the categories of equanimity (*samādhi*), naturally enter one another, spontaneously attaining the practice of bodhicitta, accomplishing equal and perfect awakening, and parinirvāṇa.' This refers to the meaning of the initial four tiers of *A*, *Ā*, *Aṃ*, and *Aḥ*; furthermore, the twenty syllables such as *ka*, *ca*, *ṭa*, *ta*, and *pa* are the meaning of the middle; the twelve syllables from *I*, *Ī* to *O*, *AU* are the meaning of the added categories of equanimity; and the twenty syllables such as *ṅa*, *ña*, *ṇa*, *na*, *ma* up to *jha*, *ja*, *ña*, *dha*, *bha* are the meaning of the final aspect.