妙法蓮華經文句 2.127

2.127

「漚鉢羅」，此云黛色蓮華池，龍依住，從池得名。本住法華三昧，迹居此池。觀者，三觀即是修因，因即蓮華也。《正法念經》云：「龍為諸天保境，修羅興兵前與龍鬪。」故知為天所管也。

"Utpalaka", translated here as "Lake of Dark Blue Lotuses"; the nāga dwells depending on it, taking his name from the lake. Originally he abides in the Lotus Samādhi, while his traces dwell in this lake. As for contemplation: the threefold contemplation is cultivating the cause, and the cause is precisely the lotus. The *Saddharmasmṛtyupasthāna-sūtra* says: "The nāgas protect the boundaries for the devas; when the asuras raise troops, they first fight with the nāgas." Thus we know they are governed by the devas.