The first altar mentioned in the Word was the one built by Noah after he came out of the ark, after being saved from the great flood. On that altar, he sacrificed clean animals to the Lord.

Mountains represent the Lord because of their height; we need to raise our thoughts above worldly things when "talking" with the Lord. An altar is a small artificial mountain. When it's used in worship, it can call to mind this raising of thought. The fire and smoke that rise from an altar are symbolically being sent to the Lord.

Most altars were made from unhewn stones. Stones represent truths. Unhewn stones - ones that have not been shaped by men - represent truths from the Word, truths that have not been adulterated.

The clean beasts to be sacrificed represent good things, charitable acts done because they are right. The clean birds represent thoughts about doctrine and actions, and about what is right. Presenting these things is an acknowledgment that we have them from the Lord, and a giving thanks to Him for them.

In the Israelitish Tabernacle, the altar of burnt offering represented the acknowledgment of good and the altar of incense that of truth. For this reason this larger altar, which was outside by the door, was made of brass which signifies natural good, while the altar of incense was made of gold, which signifies love to the Lord from whom comes truth.

790. 'Waters' here and in what follows means falsities. This becomes clear from the places in the Word quoted in the preliminary section of this chapter ¹ and from those at verse 6 of this chapter, where the flood or inundation of waters is the subject. In those places it was shown that 'inundations of waters' meant desolations and temptations, which entail the same thing as falsities, for desolations and temptations are nothing else than inundations of falsities that have been activated by evil spirits. The reason why such waters mean falsities is that generally 'waters' in the Word means that which is spiritual, that is, that which is intellectual, rational, and factual. And since waters mean these they also mean their opposites, for every falsity is a factual matter, and seemingly rational and intellectual since it is a matter belonging to thought.

[2] That 'waters' means spiritual things is clear from very many places in the Word. But that 'waters' also means falsities, let the passages that follow, in addition to those quoted already, serve to confirm the point. In Isaiah,

This people have refused the waters of Shiloah that go out gently. Therefore, behold the Lord is causing to rise up over them the waters of the river, mighty and many. And it will rise up over all its channels and go over all its banks. Isaiah 8:6-7.

Here 'waters that go out gently' stands for spiritual things, 'waters mighty and many' for falsities. In the same prophet,

Woe to the land shadowing with wings, which is beyond the rivers of Cush, sending ambassadors to the sea, and in vessels of papyrus over the face' of the waters! Go, you swift ambassadors, to a nation marked out and trodden down, whose land the rivers have spoiled. Isaiah 18:1-2.

This stands for falsities, which belong to 'the land shadowing with wings'.

[3] In the same prophet,

When you pass through the waters, I will be with you; and through the rivers, they will not overwhelm you. Isaiah 43:2.

'Waters' and 'rivers' stand for difficulties, and also for falsities. In Jeremiah,

What have you to do with the way to Egypt, to drink the waters of Shihor? And what have you to do with the way to Asshur, to drink the waters of the River? Jeremiah 2:18.

'Waters' stands for falsities arising out of reasonings. In the same prophet,

Who is this coming up like a river, like the rivers his waters are tossed about? Egypt comes up like the river, and like the rivers his waters are tossed about. And he said, I will go up, I will cover the earth, I will destroy the city and those who dwell in it. Jeremiah 46:7-8.

'Waters' stands for falsities arising out of reasonings.

[4] In Ezekiel,

Thus said the Lord Jehovah, When I make you a city laid waste, like the cities that are not inhabited, when I shall cause the deep to come up over you, and many waters have covered you, I will cause you to go down with those who go down into the Pit. Ezekiel 16:19, 20.

'Waters' stands for evils and derivative falsities. In Habakkuk,

You did trample the sea with Your horses, the mud of many waters. Habakkuk 3:15.

'Waters' stands for falsities. In John,

The dragon poured water like a stream out of his mouth after the woman, to swallow her up in the river. Revelation 11:15, 16.

Here 'waters' stands for falsities and lies. In David,

Send forth Your hands from on high, rescue me, and deliver me from the many waters, from the hands of sons of the foreigner, whose mouths speak lies, and whose right hands are right hands of falsity. Psalms 144:7-8.

Here 'many waters' clearly stands for falsities, and 'sons of the foreigner also means falsities.