John Calvin on Exodus 15:16

16. Fear and dread shall fall upon them. Some read this in the optative mood, but with little probability, as it seems to me; for Moses is not so much expressing wishes or prayers, as animating the Israelites to have a good hope, and to be firmly convinced that God would not make an end until He had finished the course of His grace. And this we may fairly apply to ourselves at this time, viz., that God will continue His calling in the elect, until they are brought on to the goal. For the heavenly inheritance, (to which we are called,) answers to “the mountain” of His holiness. Sion. — Fr. The same reason, which was just before advanced, is again repeated, viz., that God would not fail His people until the end, because He had “purchased” them to Himself. For the translation “which thou hast possessed” is not so suitable; because although Moses signifies that they are God’s peculiar people, yet is their deliverance undoubtedly alleged as the cause of their full redemption; as if he had said, that the people whom God had once undertaken to protect would always be dear to Him.