Jude 1:13

Raging waves of the sea Unstable in their doctrine, and turbulent and furious in their tempers and manners, having no command of their irascible passions. Foaming out their own shame By their wicked and outrageous behaviour, even among their disciples, showing their own filthiness to their great disgrace. The apostle seems here to have alluded to Isaiah 57:20, The wicked are like the troubled sea when it cannot rest, whose waters cast up mire and dirt. Wandering stars Πλανηται, literally, planets, which shine for a time, but have no light in themselves. The Jews called their teachers stars, and Christian teachers are represented under the emblem of stars, Revelation 1:20; Revelation 2:1. And as the planets seem to have a very irregular motion, being sometimes stationary and sometimes retrograde, they are very proper emblems of persons unsettled in their principles, and irregular in their behaviour, such as these men were. To whom is reserved the blackness of darkness, &c. Who will soon be driven to an eternal distance from the great original of light and happiness, to which they shall never return. Thus the apostle illustrates their desperate wickedness, by comparisons drawn from the air, earth, sea and heavens.