BG Chap 10 - The vibhūtis of Kṛṣṇa
(1): Kṛṣṇa is the cause of all vibhūtis in the form of His three Viṣṇu expansions for creation, maintenance and destruction of the mahat-tattva and other elements. The Viṣṇu forms are full of vibhūtis, knowledge and bliss, and are situated within the abode consisting of all elements. Kṛṣṇa is situated within the abode of prakṛti in the form of Kāraṇodakaśāyī Viṣṇu, who is the antaryāmī within this prakṛti. He is also situated as the antaryāmī of the virāṭ, the aggregate of all beings in the form of Garbhodakaśāyī Viṣṇu. He is also situated as the antaryāmī of the individuals, dwelling within their hearts in the form of Kṣīrodakaśāyī Viṣṇu. These three forms should be meditated upon understanding they are the vibhūtis of Kṛṣṇa. The first is the creator of the mahat-tattva, the second is situated in the universe and the third is situated in all jīvas.
A literal translation of this verse 10.20 would be that the Lord is the Self abiding in the hearts of all beings. Some say that this indicates the jivas are also Paramatma. But as explained before Kṛṣṇa is explaining His vibhūtis - His glories, His power - in this world and has already mentioned that He is the source of everything including the jivas, who are His para-prakrti. Even if we accept this verse indicates the non difference of the Paramatma and the jivatma, there are other verses that clearly indicate difference. Accepting both, instead of conveniently relegating the "difference verses" to the mundane realm, the philosophy of Lord Caitanya explains the acintya-bheda-abheda relationship of the Lord with the individual jivas.