大乘起信論廣釋卷第三．四．五 5.36

5.36

論。而實菩薩至僧祇劫故　釋曰。此實行不殊德也。而實菩薩等者。初正明等義。一種性等。皆入種姓菩薩位故。二諸根等。上中下根皆上根故。三發心等。發直心等。皆無別故。四所證等。皆證真如根本理故。故新論云。種姓諸根發心作證。皆悉同等。由此等故無超過法。以一切菩薩等者。後約時釋成。從初正信至於初地初無數劫。初地乃至七地滿心二僧祇。滿八地乃至十地終心三僧祇劫。既皆三祇無超過也。然僧祇數有大有小。若依小乘有六十數。一各皆劫數至百千為第一數。如是展轉十十而倍第五十二名阿僧祇。終而復始。僧祇至三名三僧祇。若依大眾有百二十數。數至百千名一俱胝。為第一。俱胝俱胝為俱梨。倍倍而數至一百亦名阿僧祇。從始至終僧祇至三名三僧祇。問。成佛要定三祇劫耶。有義成佛義定三祇劫。由種姓等皆平等故。佛大悲緣無偏為故。優婆塞經及智論說。我於往昔寶頂佛所滿足第一阿僧祇劫。然燈佛所二僧祇滿。至毘婆尸佛三僧祇圓。後九十一劫別修相好因。故知成佛定三祇劫。是故論中言皆經等。而有經說劫不定者。諸界諸佛相望而說。或隨眾生根行而言。若彼彼界彼彼諸佛定爾。所時方得成佛。有義。成佛時劫不定。諸經論說義不定故。今者略顯五義不定。一通諸方雖類世界劫數短長非定一故。二設一方前後劫數人壽短長亦不定故。三諸菩薩不唯定居一世界中行勝行故。四一切時分皆不可說一念不生即成佛故。五諸劫相入一即一切。於一念中含多劫故。而說三祇方成佛者。且隨多分。極遲者說顯長時。修功德聚。廣作期限。求理實不定。由大乘法是最勝乘。若有猛利無間修者。亦有速疾得成佛義。故金剛頂理趣等經皆說。現世登歡喜地。十六生後得成菩提。大般若說。勇猛菩薩。百劫相續便得成佛。不爾何故釋迦菩薩。放大通佛已行妙行。又如何說超於彌勒。若超小劫。大劫亦然。故不可執定三祇劫。

[Treatise:] Yet in reality, bodhisattvas […] asaṃkhyeya kalpas.
[Commentary:] This is the virtue of actual practice being non-distinct. "Yet in reality, bodhisattvas […]": first, this directly clarifies the meaning of equality. First, gotra is equal, because all enter the station of the bodhisattva gotra. Second, faculties are equal, because superior, middling, and inferior faculties are all the superior faculty. Third, arousing the mind is equal, because arousing the straightforward mind and so forth are all without difference. Fourth, what is realised is equal, because all realise the fundamental principle of suchness. Thus the New Treatise says: "Gotra, faculties, arousing the mind, and realization are all identical and equal." Because of these equalities, there is no dharma of surpassing.
"Because all bodhisattvas […]": next, this explains and establishes it in terms of time. From initial correct faith up to the first ground is the first incalculable kalpa; from the first ground up to the fulfillment of the seventh ground is two asaṃkhyeyas; fulfilling the eighth ground up to the final mind of the tenth ground is three asaṃkhyeya kalpas. Since all require three asaṃkhyeyas, there is no surpassing.
However, the number of an asaṃkhyeya has greater and lesser counts. According to the Hīnayāna, there are sixty numbers: counting kalpas up to a hundred thousand is the first number; thus proceeding, multiplying tenfold at each step, the fifty-second is named an asaṃkhyeya. When finished, beginning again, three asaṃkhyeyas are called three asaṃkhyeyas. According to the Mahāsāṃghika, there are one hundred and twenty numbers: counting up to a hundred thousand is called one koṭi, as the first; a koṭi of koṭis is a kuli; doubling and doubling the count up to one hundred is also called an asaṃkhyeya. From beginning to end, reaching three asaṃkhyeyas is called three asaṃkhyeyas.
Question: Must attaining Buddhahood definitely take three asaṃkhyeya kalpas?
One view holds: The attainment of Buddhahood is definitely three asaṃkhyeya kalpas. Because gotra and so forth are all equal, and the conditions of the Buddha's great compassion are without bias. The Upāsaka-śīla Sūtra and the Mahāprajñāpāramitopadeśa say: "In the past, under the Buddha Ratnaśikha, I completed the first asaṃkhyeya kalpa; under the Buddha Dīpaṃkara, the second asaṃkhyeya was completed; and reaching the Buddha Vipaśyin, the third asaṃkhyeya was brought to completion. Thereafter, for ninety-one kalpas, I separately cultivated the causes of the marks and signs." Therefore we know that attaining Buddhahood definitely takes three asaṃkhyeya kalpas. For this reason, the treatise says "all pass through […]". As for sūtras saying that kalpas are indefinite, they speak comparatively regarding the Buddhas of various realms, or in accordance with the faculties and practices of sentient beings. For such-and-such a realm and such-and-such Buddhas, it is fixed that only after so much time is Buddhahood attained.
Another view holds: The kalpas of time for attaining Buddhahood are indefinite, because the meaning stated across various sūtras and treatises is indefinite. Here we briefly show five indefinite aspects: first, across all directions, although worlds are of various types, the length or shortness of kalpa numbers is not fixed as one; second, even within a single direction, across earlier and later kalpas, the length of human lifespans is also not fixed; third, bodhisattvas do not abide exclusively in a single world to perform their superior practices; fourth, all time divisions are inexpressible—in a single thought-moment where non-arising occurs, Buddhahood is attained; fifth, kalpas interpenetrate: one is all, and within a single thought-moment multiple kalpas are contained. Stating that Buddhahood is attained only after three asaṃkhyeyas merely follows the majority and is spoken for the slowest, to reveal that cultivating the mass of merit takes a long time and to broadly set a limit; in seeking the true principle, it is not fixed. Because the Mahāyāna Dharma is the supreme vehicle, if there are those who cultivate vigorously without interruption, there is also the possibility of swiftly attaining Buddhahood. Therefore the Sarvatathāgatatattvasaṃgraha and other sūtras all state that in the present life one ascends the Ground of Joy, and after sixteen births attains bodhi. The Great Prajñāpāramitā states that a vigorous bodhisattva, continuing for a hundred kalpas, directly attains Buddhahood. Otherwise, why would the bodhisattva Śākyamuni have already practiced wondrous deeds under the Buddha Mahābhijñājñānābhibhū? And how could it be said that he surpassed Maitreya? If he surpassed small kalpas, the same applies to great kalpas. Therefore, one must not grasp that three asaṃkhyeya kalpas is fixed.