ἀνάγκᾳ δ' οὐδὲ θεοὶ μάχονται → but not even gods fight necessity (Simonides, fr. 37.1.29)
of the sea: Ar. and V. σάλος, ὁ.
heaving motion: P. αἰώρησις, ἡ (Plato).