1 Gita Sloka Every Day - Chapter 13 - Kshetra Kshetrajna Yoga - Sloka 31

The entire content of this mail is from Swami Adidevananda's translation of Ramanuja's  Gita  Bhashya and Swami Chidbhavananda's Bhagavad Gita, both published by Ramakrishna Mission

Do the activities of prakriti affect Brahman? The elucidiation comes.

Brahman is Self sufficient 31-34

1 Gita Sloka  Every Day - Chapter 13 - Kshetra Kshetrajna Yoga - Sloka 31

The body changes but the soul remains the same

Anadi tvat nirguna tvat paramatma ayam avyayah I

Sharira stah api kaunteya na karoti na lipyate II sloka 31

अनादि त्वात् निर्गुण त्वात्  परमात्मा अयम् अव्ययः I 

शरीर स्तः अपि कौन्तेय न करोति न लिप्यते  II श्लोक 31

This supreme self  though dwelling in the  body, is immutable, O Arjuna, being without beginning. It neither acts nor is tainted, as it is without gunas.

This 'supreme self' (atman) has been defined as having a nature different from that of the body. While existing in the body, it is immutable ie. it is not liable to decay as it is 'without a beginning', ie. never created at any point of time. Because it is free from gunas, being devoid of sattva and other gunas of prakriti. It neither acts nor gets tainted; It is not tainted by the qualities of the body.