B.G 3.30

mayi sarvāṇi karmāṇi saṁnyasyādhyātmacētasā। nirāśīrnirmamō bhūtvā yuddhyasva vigatajvaraḥ ॥30॥

Having no selfish desire, having no notion of agency, dedicating all actions to Me become 'ādhyātma cētasā', i.e. one who understands lord only as the doer and surrenders the self to Bhagavan. With this understanding, engage in the battle with no fear.

Gīta Bhāshya 3.30

'saṁnyāsa' - having the understanding that the lord (Bhagavan) only acts. 'ādhyātma cētasā' - one who surrenders his 'atman' to Bhagavan. 'nirmama' - having the understanding that I am not the doer.

ataḥ sarvāṇi karmāṇi mayyēva saṁnyasya bhrāntyā jīvē adhyārōpitāni mayyēva visr̥tya, bhagavānēva sarvāṇi karmāṇi karōtīti matpūjēti ca। ātmānaṁ mām adhikr̥tya yaccētaḥ tat adhyātmacētaḥ। saṁnyāsastu bhagavān karōtīti। nirmamatvaṁ nāhaṁ karōmīti ॥30॥

Therefore, renounce all actions in Me only, i.e. having abandoned the superimposed notion that I am the doer arising due to delusion, having understood the lord (Bhagavan) as the real doer of all actions, worship Me. The one who surrenders his 'atman' to Me is the 'ādhyātma cētasā'. 'saṁnyāsa' in this context means having the understanding that the lord (Bhagavan) only acts. 'nirmama' mans having the understanding that I am not the doer