《太上洞玄灵宝天尊说大通经》

It comes into being before Heaven and Earth, yet has no form; after Heaven and Earth appear, it still abides, and still has no substance. Thus, although it is without substance, one cannot simply say that it exists, and so it is called inconceivable.

Stillness is original nature, and the mind abides within stillness. Movement is the functioning of the mind, and original nature likewise resides in the mind. When thoughts arise, original nature seems to recede; when thoughts subside, original nature then appears. It is like empty space, without fixed form, clear and still, perfectly harmonious and complete.

The Great Dao (the Way) has no fixed image, and so can inwardly encompass all things that have form. True original nature is Wuwei (non-action), and so does not give rise outwardly to a deluded mind. It is spontaneous, vast, and boundless. Facing external conditions without clinging to them, one is not confused by the “six thieves” (the eyes, ears, nose, tongue, body, and mind—the senses and thoughts that disturb the mind and Shen (spirit)). Dwelling in the dusty world yet able to transcend the mundane, one is not drawn along and altered by the multitude of affairs. Bring the mind to utmost stillness, and it is not moved by external things; bring the mind to equanimity, and it does not shift with circumstances. The light of wisdom illuminates the ten directions (every direction), transforming and functioning within emptiness and stillness without falling into deliberate contrivance.

The verse says:

From within existent dharma, awaken to non-dharma; understand cultivation and arrive at non-cultivation. The original substance that embraces the myriad phenomena clings not to the slightest trace.