首楞嚴義疏注經 8.119

8.119

法界心地即前一心，妙行能涉，妙智能知，理、智、行三自在圓融，不以二邊之所住著，名無留礙，此真修行，名修行住。

The ground of the mind of the dharmadhātu is the aforementioned one mind; wondrous practice can step upon it, and wondrous wisdom can know it. Principle, wisdom, and practice—the three are sovereign and completely interfused, not dwelling upon or clinging to the two extremes; this is called being free from hindrance. This is true practice, called the Abode of Practice.