B.G 3.28
तत्त्ववित्तु महाबाहो गुणकर्मविभागयोः। गुणा गुणेषु वर्तन्त इति मत्वा न सज्जते ॥२८॥
tattvavittu mahābāhō guṇakarmavibhāgayōḥ। guṇā guṇēṣu vartanta iti matvā na sajjatē ॥28॥
But O Mighty armed, he who has the ability to differentiate the different types of qualities and actions is the knower of principles. Understanding the qualities (of five senses, five organs, and the mind) engage themselves in their respective topics, he does not get attached.
Gīta Bhāshya 3.28
tattvavit - one who has the ability to differentiate between different types of qualities and actions; guṇā - qualities of the Indriyas (i.e. qualities of five senses, five actions and the mind); guṇēṣu - respective topics that the Indriyas engage in;
One becomes the knower of principles by differentiating actions and their respective qualities. 'guṇā' refers to qualities of the Indriyas (i.e. qualities of five senses, five actions and the mind). 'guṇēṣu' refers to respective topics that the Indriyas engage in.