sarva-dvaresu dehe ’smin
jnanam yada tada vidyad
vivrddham sattvam ity uta
The manifestations of the mode of goodness can be experienced when all the gates of the body are illuminated by knowledge.
Commentary by Srila Prabhupada
There are nine gates in the body: two eyes, two ears, two nostrils, the mouth, the genitals and the anus. When every gate is illuminated by the symptoms of goodness, it should be understood that one has developed the mode of goodness.
In the mode of goodness, one can see things in the right position, one can hear things in the right position, and one can taste things in the right position. One becomes cleansed inside and outside. In every gate there is development of the symptoms of happiness, and that is the position of goodness.
Commentary by Sri Visvanatha Cakravarti Thakur
It has been stated that the prominent guna overshadows the other two gunas, which have become weak of their own accord. Now the Lord speaks of the qualities of increasing gunas in three verses. When illumination or knowledge, real awareness of things through the sound of the Vedas, appears in all the doors such as the ears, one should understand there is an increase in sattva through such symptoms of knowledge. The word uta (also) indicates there will also be an appearance of happiness arising from the soul. When knowledge and happiness appear,. one should understand there is an increase in sattva.