The Diamond Sutra, also known as the *Vajracchedikā Prajñāpāramitā Sūtra*, is one volume from the vast collection of the Prajñāpāramitā (Perfection of Wisdom) scriptures, which span six hundred volumes in total. Though concise in wording, its meaning is profound and precise, aptly compared to the hardest substance within gold—hence its name. The six hundred volumes of the Prajñāpāramitā literature are vast and deep, often challenging for readers. Yet this single volume is recited in households far and wide, allowing the profound meaning of Prajñāpāramitā to be widely propagated.

Since ancient times, there have been no fewer than a hundred commentaries on this sutra. Those with divergent views need not be discussed here. Among those that align with its true meaning, the most esteemed are the three treatises by Asaṅga, Vasubandhu, and Śāntarakṣita, as well as the three commentaries by Sengzhao, Zhiyi, and Jiaxiang. Later works by masters such as Zongle, Hanshan, Ouyi, and Xufa each contain their own refined insights, yet they largely remain within the scope of the ancient commentaries. However, none compare to the exceptional depth and breadth of layman Jiang Weinong’s *Lectures on the Diamond Sutra*.

The *Lectures* not only elucidate the essential principles of Prajñāpāramitā in thorough and exhaustive detail but also draw connections with other major Mahāyāna sutras. In guiding practitioners in the methods of contemplation, it goes beyond merely expounding the advanced practices of Chan and the single-minded focus of Pure Land—it also reveals what previous commentators had not yet articulated. Particularly insightful is the author’s view that, whereas the Tiantai school classifies this sutra as encompassing both general and specific teachings along with the perfect teaching, and the Huayan school categorizes it within the initial teachings, Jiang alone judges it to be a teaching of supreme perfection and immediacy. This accords well with the sutra’s own declaration that the Tathāgata expounded it for those of the highest capacity.

Moreover, regarding phrases in the sutra such as “Tathāgata,” “Buddha,” “World-Honored One,” “not so,” and “the Buddha addressed Subhūti”—often overlooked by ordinary readers—Jiang is able to illuminate their profound meanings. Recently, the Shengxin Lotus Society printed this *Lectures*, and I assisted in its proofreading. Upon reading the text, I could not help but feel joyful and uplifted, exclaiming that such a work had never before existed. Additionally, by consulting ancient editions to verify variant characters and establish a definitive version, Jiang has rendered an invaluable service to this sutra spanning over a thousand years.

Previously, when reading layman Huang Hanzhi’s *Vernacular Explanation of the Amitābha Sutra*, I remarked: “Those who study this explanation will not only understand the meaning of the Amitābha Sutra but also grasp the principles of all sutras.” Now I say the same of Jiang’s *Lectures on the Diamond Sutra*. With the circulation of these *Lectures*, I am confident that readers, upon opening this volume, will gain insight equivalent to studying tens or hundreds of other sutras. As the sutra itself states, “All Buddhas and the Dharma of all Buddhas arise from this sutra”—is this not clearly and evidently demonstrated?

Having completed the proofreading, I offer this preface in praise and admiration.

Respectfully composed by Fan Gunong (He Nan) In the early summer of the Gengchen year, the 29th year of the Republic of China.