大方廣圓覺修多羅了義經略疏 1.730

1.730

此印前也。幻謂虛幻，無有實體。垢謂塵垢，坌污為名。由迷幻相，執取繫著，坌污淨心，故云幻垢。諸佛菩薩雖有身心，由了如幻，不取於相，無坌污義，故非垢；由了幻空，故非幻。

This confirms what preceded. 'Illusory' means empty and illusory, possessing no real substance. 'Grime' means dust and grime, named for defiling and staining. Due to delusion regarding illusory marks, one grasps and attaches to them, defiling the pure mind; hence they are called 'illusory grime.' Although all buddhas and bodhisattvas have bodies and minds, because they comprehend that they are like illusions, they do not grasp at marks and there is no meaning of defilement; hence they are not grime. Because they comprehend that illusions are empty, they are not illusory.