B.G 5.07
Yōgayukto viśuddhātmā vijitātmā jiteṁdriyaḥ। sarvabhūtātmabhūtātmā kurvannapi na lipyate ॥7॥
That pure being who is engaged in Yoga, is specially victorious having conquered all the faculties and has the understanding that 'the lord of all beings is also my lord'. Faults do not affect such a person, even if they engage in action.
Gīta Bhāshya 5.07
The Lord is the master of all beings. Such a lord is within me, and enables all the activities of mine. Such an understanding is 'sarvabhūtātma bhūtātmā'.
etadeva prapañcayati - Yōgayuktaḥ iti। sarvabhūtātma bhūtaḥ parameśvaraḥ। 'yaccāpnoti' ityādeḥ। sa ātmabhūtaḥ svasamīpaṁ prati ādānādikartā yasya saḥ sarvabhūtātma bhūtātmā ॥7॥
The verse 'Yōgayuktaḥ', i.e. one engaged in Yōga, explains the state of the person engaged in Yōga. The Supreme Lord, Parameshwara, is the becoming and essence of all beings. It is explained by verses such as 'yaccāpnoti' (Linga puranam 1.70.96), i.e. 'whatever one achieves'. He is the essence of beings; He is the one who is near oneself; one who enables all the activities of the beings. Such an understanding is "sarvabhūtātma bhūtātmā", i.e. "the essence of all beings and that of individual being as well".
"यच्चाप्नोति यदादत्ते यच्चात्ति विषयानिह । यच्चास्य सन्ततो भावयस्तस्मादात्मेति कीर्त्यते॥" - Linga puranam 1.70.96
"Whatever one achieves, receives, and eats, as well as whatever objects one regularly thinks of, of Him, therefore, the Ātman is celebrated as such."