法華義疏 4.21

4.21

大是具足方廣，小是隨分方廣。又大乘理正曰方，義富稱廣，文詮方廣之理名為方廣經。小乘語正曰方，文多稱廣也。

The Mahāyāna is the complete vaipulya, while the Hīnayāna is vaipulya according to its capacity. Furthermore, in the Mahāyāna, the correct principle is called 'square' (vai-), and the abundance of meaning is called 'broad' (-pulya); texts that express this principle of vaipulya are called vaipulya sūtras. In the Hīnayāna, correct speech is called 'square,' and the multitude of texts is called 'broad.'