Master, Master (Επιστατα, επιστατα). See on Luke 5:5 for discussion. Mark 4:38 has

Teacher (Διδασκαλε), Matthew 8:25 has

Lord (Κυριε). The repetition here shows the uneasiness of the disciples.

We perish (απολλυμεθα). So in Mark 4:38; Matthew 8:25. Linear present middle indicative, we are perishing.

The raging of the water (τω κλυδον του υδατος). Κλυδων, common Greek word, is a boisterous surge, a violent agitation. Here only in the N.T. save James 1:6. Κυμα (Mark 4:37) is the regular swell or wave. A calm (γαληνη). Only in the parallels in the N.T., though common word. Here Mark 4:39; Matthew 8:26 add great (μεγαλη).

That (οτ). This use of οτ as explanatory of the demonstrative pronoun ουτος occurs in the parallels Mark 4:36; Matthew 8:27 and also in Luke 4:36. It is almost result.

He commandeth (επιτασσε). Peculiar to Luke.