大方廣圓覺修多羅了義經略疏 1.786

1.786

六皆名塵者，坌污心識故，約凡夫說也。亦云六境，此通凡聖。言色等者，眼等所取故。色有通別，今即別也，謂唯眼所取，有見有對，變礙之相，最麁顯故，聲等可知。唯意所取法塵一境通於一切。

All six are called 'dust' because they defile the mind and consciousness, spoken in terms of ordinary beings. They are also called the six objects, which applies to both ordinary beings and noble ones. Speaking of 'form and the rest,' they are what is grasped by the eye and other faculties. 'Form' has general and specific meanings; here it is the specific, referring exclusively to what is grasped by the eye, possessing visibility and resistance, being the mark of change and obstruction, because it is the most coarse and obvious; sound and the rest can be known accordingly. The single object of the dharma dust grasped exclusively by the mind pervades everything.