What the Bible says about Epistates
(From Forerunner Commentary)
Two miracles of Jesus Christ recorded in Scripture tell of Him calming storms on the Sea of Galilee. The first miracle of this type appears in Matthew 8:23-27; Mark 4:35-41; and Luke 8:22-25. For Jesus, this is a day of both significant teaching, including the seven parables of Matthew 13, and considerable testing. He is sought by concerned friends, His mother, and half-brothers, and is accused of being demon-possessed by some who think that He is not in His right mind.
These things, along with performing this miracle, leave Jesus physically and mentally tired. Mark indicates that He shows signs of fatigue from incessant interruptions and distractions by the people pursuing Him. Yet, He unselfishly gives Himself to serve others. Because of the large crowds still gathering around Him, He tells His disciples to take Him in their small boat to the quieter region of Perea across the Sea of Galilee.
Once on board, Jesus falls asleep on a pillow, an item normally found among the sparse furnishings of that type of boat. A storm rises suddenly, terrifying the disciples. Mark describes the waves beating into the boat and filling it. Luke expresses the disciples' urgency by repeating the Greek word epistates, which means "Master, Master!" or "Rabbi, Rabbi!" However, because of His complete trust in His Almighty Father's care and protection, and His knowledge that He had God-given power over the winds and the sea, Jesus remains peacefully asleep.
Martin G. Collins
The Miracles of Jesus Christ: Stilling a Storm