Śrīmad-Bhāgavatam · Text 5.18.30
Who is speaking and story frame
ॐ नमो भगवते अकूपाराय सर्वसत्त्वगुणविशेषणायानुपलक्षितस्थानाय नमो वर्ष्मणे नमो भूम्ने नमो नमोऽवस्थानाय नमस्ते ॥ ३० ॥
oṁ namo bhagavate akūpārāya sarva-sattva-guṇa-viśeṣaṇāyānu-palakṣita-sthānāya namo varṣmaṇe namo bhūmne namo namo ’vasthānāya namas te.
O my Lord, I offer my respectful obeisances unto You, who have assumed the form of a tortoise. You are the reservoir of all transcendental qualities, and being entirely untinged by matter, You are perfectly situated in pure goodness. You move here and there in the water, but no one can discern Your position. Therefore I offer my respectful obeisances unto You. Because of Your transcendental position, You are not limited by past, present and future. You are present everywhere as the shelter of all things, and therefore I offer my respectful obeisances unto You again and again.
Read Śrīla Prabhupāda's purport on Vedabase.io