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.

2455. That 'she became a pillar of salt' means that all good accompanying truth was vastated becomes clear from the meaning of 'a pillar' and from the meaning of 'salt'. In the original language the word used for a pillar means something standing still, not however that used for a pillar which was erected either for worship, or as a sign or for a witness. Consequently 'the pillar of salt' mentioned here means that it - the truth meant by Lot's wife - stood as something vastated, 2454. Truth is said to be vastated when it no longer has any good within it - vastation itself being meant by 'salt'.

[2] As most things in the Word have two meanings, namely the genuine and the contrary to this, so also does 'salt'. In the genuine sense it means the affection for truth, in the contrary sense the vastation of the affection for truth, that is, of the good within truth. That 'salt' means the affection for truth, see Exodus 30:35; Leviticus 2:13; Matthew 5:13; Mark 9:49-50; Luke 14:34-35. That it also means the vastation of the affection for truth, that is, of the good within truth, is clear from the following places: In Moses,

The whole land will be brimstone and salt, a burning; it will not be sown, it will not sprout, nor will any plant come up on it, as at the overthrow of Sodom and Gomorrah, of Admah and Zeboiim. Deuteronomy 29:23.

Here 'brimstone' is the vastation of good, and 'salt' the vastation of truth. That vastation is the meaning is evident from each detail.

[3] In Zephaniah,

Moab will be like Sodom, and the children of Ammon like Gomorrah, a place abandoned to the nettle, and a saltpit, and a desolation for ever. Zephaniah 2:9.

Here 'a place abandoned to the nettle' stands for vastated good, 'a salt pit' for vastated truth; for 'a place abandoned to the nettle' refers to Sodom, which has been shown to mean evil or vastated good, and 'a salt pit' to Gomorrah, which has been shown to mean falsity or vastated truth. That vastation is the meaning is evident from its being called 'a desolation for ever'. In Jeremiah,

He who makes flesh his arm will be like a bare shrub in the solitary place and will not see when good comes; and he will inhabit the parched places in the wilderness, a salt land and not inhabited. Jeremiah 17:5-6.

Here 'a parched land' stands for vastated goods, 'a salt land' for vastated truths.

[4] In David,

Jehovah turns rivers into a wilderness, and outgoings of waters into a dryness, a fruitful land into a salty waste because of the wickedness of those inhabiting it. Psalms 107:33-34.

'A fruitful land into a salty waste' stands for the vastation of the good within truth. In Ezekiel,

Its swamps and its marshes are not healed, they will be given up to salt. Ezekiel 47:11.

'Given up to salt' stands for being utterly vastated as regards truth. Because 'salt' meant vastation and 'cities' matters of doctrine concerning truth, as shown in 402, 2268, 2428, 2451, cities that had been destroyed were in former times sown with salt to prevent their being rebuilt, Judges 9:45. The description at this point is of the fourth state of the Church represented by 'Lot', a state in which all truth has been vastated as regards good.