611. But in the days of the voice of the seventh angel, when he is about to sound.- That this signifies the last state of the church, and then revelation of Divine Truth, is evident from the signification of the days of the voice of the seventh angel, as denoting the last state of the church; for the progressive changes of the state of the church are described by the sounding of the seven angels, therefore the voice of the seventh angel signifies the last state; and from the signification of, when he is about to sound, as denoting revelation then of Divine Truth. That by sounding a trumpet or horn is signified the influx of Divine Truth, and its revelation, may be seen above (n. 502). That its revelation is here signified, is evident from the following part of this verse, where it is said, "And the mystery of God shall be consummated, as he hath declared in good tidings to his servants the prophets." This signifies that the prediction concerning the coming of the Lord shall then be fulfilled. With the coming of the Lord there is also revelation of Divine Truth.

Water generally represents “natural truth,” or true concepts about day-to-day matters and physical things. Since all water ultimately flows into the seas, then, it follows that a sea represents a huge agglomeration of such natural truths -- usually all of the natural truth a person has, or all the natural truth a church has. Water in the sea mixes freely, and is easily stirred up by winds and currents. This is also true of the concepts we hold about natural things -- they are not all related to each other, and when relationships do exist they usually can change without damaging the concepts themselves. Many of the concepts are easily disputed, and arguments can arise like waves on the ocean -- generally with little effect other than a mixing of waters. But the sea also offers great bounty. We draw fish from it (spiritual food), float ships (doctrinal systems) on it, bathe in it (using true concepts to purify ourselves), and the water that evaporates from it and falls as rain (purer forms of truth that can attach to desires for good) makes life possible.