And Israel saw that great work which the Lord did upon the Egyptians: and the people feared the Lord, and believed the Lord, and his servant Moses. (Exodus 14:31)

His power, appeared, because there was no difficulty in distinguishing between God’s wrath and His fatherly love, in preserving so miraculously an unwarlike multitude, and in destroying in the depths of the sea an army formidable on every account. Moses, therefore, does not unreasonably conclude here that the Divine power was conspicuous in the deliverance of the people. He afterwards adds, that, not without their profit, did the Israelites see God’s hand; because they feared Him, and believed Him, and His servant Moses. “Fear” is here used for that reverence which kept the people in the way of duty, for they were not only affected by dread, but also attracted to devote themselves to God, whose goodness they had so sweetly and delightfully experienced. But although this pious feeling was not durable, at any rate with the greater number of them, it is still probable that it rooted itself in some few of them, because some seed ever remained, nor was the recollection of this blessing entirely destroyed. By the word “believed,” I think that the principal part of fear is marked, and I understand it to be added expositively, as if it were said, “that they reverenced God, and testified this by faithfully embracing His doctrine and obediently submitting themselves to Moses.” I understand it that they were all generally thus affected, because the recognition of God’s hand bowed them to obedience, that they should be more tractable and docile, and more inclined to follow God. But this ardor soon passed away from the greater number of them, as (hypocrites [161] ) are wont to be only influenced by what is visible and present; although I hold to what I have just said, that, in some small number, the fear of God, which they had once conceived from a sense of His grace, still abode in rigor. Meanwhile, let us learn from this passage that God is never truly and duly worshipped without faith, because incredulity betrays gross contempt of Him; and although hypocrites boast of their heaping all kinds of honor upon God, still they inflict the greatest insult upon Him, by refusing to believe His revelations. But Moses, who had been chosen God’s minister for governing the people, is not unreasonably here united with Him, for although God’s majesty manifested itself by conspicuous signs, still Moses was the mediator, out of whose mouth God willed that His words should be heard, so that the holy man could not be despised without God’s own authority being rejected. A profitable doctrine is gathered from hence, that whenever God propounds His word to us by men, those who faithfully deliver His commands must be as much attended to as if He himself openly descended from heaven. This recommendation of the ministry ought to be more than sufficient to refute their folly, who set at naught the outward preaching of the word. Let us, then, hold fast this principle, that only those obey God who receive the prophets sent from Him, because it is not lawful to put asunder what He has joined together. Christ has more clearly expressed this in the words, — “He that heareth you, heareth me; and he that despiseth you, despiseth me.” (Matthew 10:40.)

-John Calvin, Commentary on Exodus 14:31

I am a Reformed Presbyterian. I offer all content as my own personal reflections. I am not a licensed minister.