法華經義記 5.43

5.43

第一所以言慧命須菩提者，凡有二種解，一者言昔日未解開三顯一同歸之理，愚癡之人心相續為命，今日既得解權實之宗，慧心相續為命，若爾亦應言慧命迦旃延乃至慧命目犍連，所以單道須菩提者，此則互舉為論。二者須菩提解空第一，空慧為命，《大品》座席之時已為諸菩薩轉說般若，以此呼為慧命須菩提，此即從本受名。

Regarding the first, as to why it says “the Venerable Subhūti”, there are altogether two kinds of explanations. One says that formerly, not having understood the principle of opening the three and revealing the One in identical convergence, the continuum of a foolish mind served as life; now, having attained understanding of the tenets of expedient and real, the continuum of a wise mind serves as life. If so, it should also say “the Venerable Kātyāyana” and so forth, down to “the Venerable Maudgalyāyana”; the reason why only Subhūti is mentioned is that they are cited alternately for discussion. Second, Subhūti was foremost in understanding emptiness, taking the wisdom of emptiness as life; at the assembly of the Pañcaviṃśatisāhasrikā Prajñāpāramitā, he had already turned the wheel and preached prajñā for the bodhisattvas; on this account he was called the Venerable Subhūti. This is receiving the name from his original role.