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.

9827. 'And a turban' means intelligence and wisdom. This is clear from the meaning of 'a turban' as intelligence and wisdom. 'A turban' has this meaning because it is a covering for the head, and 'the head' means a person's inward powers, which are those of intelligence and wisdom, 9656. All items of clothing derive their meaning from that part of the body which they cover, as for example with an item of clothing that covers the breast, such as a breastplate; those that cover the loins, such as trousers; those that cover the feet, such as stockings; those that cover the soles of the feet, such as sandals; and so also one that covers the head, such as a turban, headdress, or cap.

[2] The truth of all this is clear from representatives in the next life. There, when wisdom and intelligence are taken away from spirits, which happens when angelic communities are removed from them, the covering on their head is seen to be taken away from them. Once this has been done a spirit becomes stupid, devoid of any perception of what is true and good. But afterwards, as intelligence and wisdom return, his head is covered again. But items of clothing on the head there mean not so much wisdom belonging to good as intelligence belonging to truth. The turban that belonged to Aaron however means wisdom as well, since it was made from fine linen, and a holy crown was placed on it, which was a plate made from pure gold, on which Holiness to Jehovah was engraved, described further on in verses 37, 39, of the present chapter, and also Exodus 29:6; 39:28. But the turban of [ordinary] linen, and the rest of the garments of [such] linen which were also Aaron's, meant intelligence belonging to truth, but not wisdom belonging to good. Regarding those garments and that turban, see Leviticus 16:4; Ezekiel 44:18. For 'linen' or 'flax' means truth in the natural level of a person's mind, 7601, so that 'a turban of [ordinary] linen' means intelligence there.

[3] People who have no knowledge of the nature of representatives and correspondences can scarcely be brought to believe that such things are meant. But let them weigh up this, that in heaven spiritual realities are envisaged instead of natural things, so that instead of a turban, and in general instead of garments, such things are envisaged as belong to intelligence and wisdom, also to faith and love, in general such as belong to truth and goodness. For all these are spiritual, since heaven is a spiritual world. Let them also weigh up this, that it was Jehovah on Mount Sinai who described and decreed what Aaron's garments should be, which being so, every detail of the description holds within itself the Divine Celestial, which is disclosed solely by means of knowledge about correspondences and representatives.