Dear Dominik,

Whatever the history of the ban on sea travel, the “bank” (of a river, but also of an ocean) metaphor is also used to describe learned people. See pāradṛśvan (M-W: “one who has seen the oppositive shore, far-seeing, wise, completely familiar with or versed in”), i.e. one who understood the whole thing. Droṇa for instance is described in a Pallava inscription as bāṇāstravedacaturarṇṇavapāradr̥śvā, literally “who has seen the other bank of the fourfold ocean that the Veda about the bow is.”

Attaining mokṣa is reaching the other bank of the “ocean of saṃsāra”. In a buddhist context, the Buddha recollected all his previous lifes, before his nirvāṇa.

As for more on ocean as vastness, totality, completude, see the title Kathāsaritsāgara, or the very conventional description in epigraphy of universal sovereigns as ruling or being famous up to the three/four/seven oceans, i.e. in the whole world. See also some of the birudas of Narasiṃhavarman II Pallava (8^th c.): Jñānasāgara, “Ocean of knowledge”, Kalāsamudra, “Ocean of artistic skills”.

With very best wishes.

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