大乘起信論裂網疏 2.87

2.87

This is precisely the mark of pure wisdom produced when original awakening accords with defilement and discriminates. Although revealed through initial awakening, it is not different from original awakening in entanglement; it is the attribute of the Mahāyāna. Being free from the two hindrances of afflictions and the knowable reveals the meaning of genuine emptiness within the aspect of tathatā. The original nature being pure and abiding reveals genuine non-emptiness within the aspect of tathatā. To reveal the mark of non-emptiness, emptiness is established; therefore it is simply named the great meaning of genuine non-emptiness free from hindrances. This is like the great sky without clouds, or an ancient mirror polished and shining.