SB 3.6.8

eṣa hy aśeṣa-sattvānām
 ātmāṁśaḥ paramātmanaḥ
ādyo ’vatāro yatrāsau
 bhūta-grāmo vibhāvyate
Synonyms: 
eṣaḥ — this; hi — certainly; aśeṣa — unlimited; sattvānām — living entities; ātmā — Self; aṁśaḥ — part; parama-ātmanaḥ — of the Supersoul; ādyaḥ — the first; avatāraḥ — incarnation; yatra — whereupon; asau — all those; bhūta-grāmaḥ — the aggregate creations; vibhāvyate — flourish.
Translation: 
The gigantic universal form of the Supreme Lord is the first incarnation and plenary portion of the Supersoul. He is the Self of an unlimited number of living entities, and in Him rests the aggregate creation, which thus flourishes.
Purport: 

The Supreme Lord expands Himself in two ways, by personal plenary expansions and separated minute expansions. The personal plenary expansions are viṣṇu-tattvas, and the separated expansions are living entities. Since the living entities are very small, they are sometimes described as the marginal energy of the Lord. But the mystic yogīs consider the living entities and the Supersoul, Paramātmā, to be one and the same. It is, however, a minor point of controversy; after all, everything created rests on the gigantic virāṭ or universal form of the Lord.