The works of Ādi Śaṅkarācārya

Viṣṇusahasranāmastotram

Verse 54

एवमेकाग्रचित्तः सन्संस्मरन्मधुसूदनम् ।जन्ममृत्युजराग्राहं संसाराब्धिं तरिष्यति ॥

In plain words

Thus with a single-minded focus, constantly remembering Madhusūdana, one will cross beyond the ocean of worldly existence whose snapping crocodiles are birth, old age, and death.

Close to the Sanskrit

Thus being with a one-pointed mind, remembering Madhusūdana, he will cross the ocean of saṃsāra whose alligator is birth, death, and old age.