One verse

Srimad Bhagavatam 3.5.23

3.5.23

भगवानेक आसेदमग्र आत्मात्मनां विभु: । आत्मेच्छानुगतावात्मा नानामत्युपलक्षण: ॥ २३ ॥

bhagavan eka asedam agra atmatmanam vibhuh atmecchanugatav atma nana-maty-upalaksanah

bhagavan
the Personality of Godhead
ekah
one without a second
asa
was there
idam
this creation
agre
prior to the creation
atma
in His own form
atmanam
of the living entities
vibhuh
master
atma
Self
iccha
desire
anugatau
being merged in
atma
Self
nana-mati
different vision
upalaksanah
symptoms.

The Personality of Godhead, the master of all living entities, existed prior to the creation as one without a second. It is by His will only that creation is made possible and again everything merges in Him. This Supreme Self is symptomized by different names.