A.T. Robertson Commentary Acts 27:41

"But lighting upon a place where two seas met, they ran the vessel aground; and the foreship struck and remained unmoveable, but the stern began to break up by the violence [of the waves]." — Acts 27:41 (ASV)

But lighting upon (περιπεσοντες δε). Second aorist active participle of περιπιπτω, old verb to fall into and so be encompassed by as in Lu 10:30; James 1:2. There is a current on one side of St. Paul's Bay between a little island (Salmonetta) and Malta which makes a sand bank between the two currents. Unexpectedly the ship stuck in this sandbar.

Where two seas met (διθαλασσον). Used in Strabo and Dio Chrysostom for divided seas (δισ, θαλασσα).

They ran the vessel aground (επεκειλαν την ναυν). First aorist active indicative of old verb επικελλω, to run a ship ashore. Only here in N.T. Here also we have the only N.T. use of ναυς for ship (from ναω, νεω, to swim) so common in ancient Greek. Our word navy is from this word through the Latin.

Struck (ερεισασα). First aorist active participle of ερειδω, old verb to fix firmly. Only here in N.T.

Unmoveable (ασαλευτος). From α privative and σαλευω to shake. Old word. In N.T. only here and Heb 12:28.

Began to break up (ελυετο). Inchoative imperfect passive of the old verb λυω, to loosen. The prow was stuck in the sand-bar, and the stern was breaking to pieces by the opposing waves lashing on both sides. It was a critical moment.