A.T. Robertson Commentary Matthew 8:24

"And behold, there arose a great tempest in the sea, insomuch that the boat was covered with the waves: but he was asleep." — Matthew 8:24 (ASV)

But he was asleep (αυτος δε εκαθευδεν). Imperfect, was sleeping. Picturesque scene. The Sea of Galilee is 680 feet below the Mediterranean Sea. These sudden squalls come down from the summit of Hermon with terrific force (σεισμος μεγας) like an earthquake. Mark and Luke (Luke 8:23) term it a whirlwind (λαιλαπς) in furious gusts.