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.

8648. 'After he had sent her away' means a separation existing up to now in respect of the state of those belonging to the spiritual Church. This is clear from the meaning of 'sending away' as a separation. The reason why this is in respect of the state of those belonging to the spiritual Church is that in the first state of those who belong to the spiritual Church good is not apparent, only truth. The nature of all this may be seen from what has been shown previously about the two states of those belonging to the spiritual Church, that is to say, where it has been shown that in the first state actions spring from truth, not from good, but that in the second they do spring from good. In the first state, when actions spring from truth, not from good, good is seemingly absent; it is like a wife who has been sent away. But in the second state, when actions spring from good, good is present, and is like a wife joined to her husband (vir). These are the things that are meant in the internal sense by 'sending her away'.

[2] It should in addition be recognized that this is in respect of those who belong to the spiritual Church; for truth coming from the Lord is always joined to its own good. But in the first state, which exists before regeneration, good is not received, only truth, even though both flow in from the Lord by way of heaven. But in the second state, which exists after regeneration, good joined to truth is received. What is brought about by man is said to be something done by the Lord, for the reason that He appears to be the one bringing it about. The situation is the same with very many other things said of the Lord, such as when He is said to do ill, punish, and cast into hell; these things are said to be done by the Lord, because He appears to be the one who brings them about, when in fact everything bad that happens to a person is of human origin. Things like these said of the Lord in the Word are very many, but they are made clear to one who searches the Scriptures with an affection for truth and for the sake of leading a good life; for he is enlightened by the Lord.