{But lighting upon} (peripesontes de). Second aorist
active participle of peripipt(935c), old verb to fall into and so be
encompassed by as in  Lu 10:30  Jas 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}
(dithalasson). Used in Strabo and Dio Chrysostom for divided
seas (dis, thalassa). {They ran the vessel aground} (epekeilan
t(886e) naun). First aorist active indicative of old verb
epikell(935c), to run a ship ashore. Only here in N.T. Here also we
have the only N.T. use of 
aus for ship (from 
a(932c) ne(935c), to
swim) so common in ancient Greek. Our word navy is from this word
through the Latin. {Struck} (ereisasa). First aorist active
participle of ereid(935c), old verb to fix firmly. Only here in N.T.
{Unmoveable} (asaleutos). From a privative and saleu(935c) to
shake. Old word. In N.T. only here and  Heb 12:28 . {Began to
break up} (elueto). Inchoative imperfect passive of the old
verb lu(935c), 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.