The works of Ādi Śaṅkarācārya

Viṣṇusahasranāmastotram

Verse 182

यदक्षरं वेदविदो वदन्ति विशन्ति यद्यतयो वीतरागाः ।

In plain words

The Imperishable — that is what those who know the Veda call it; and that is what ascetics enter, once every trace of rāga has fallen away —

Close to the Sanskrit

Which imperishable the knowers of the Veda speak of, which the ascetics whose attachment has gone away enter —