921. 'Noah built an altar to Jehovah' means a representative of the Lord. This is clear from what has been stated just above. All the religious observances of the Ancient Church were representative of the Lord, as also were those of the Jewish Church. But the chief representative in later times was the altar, and also the burnt offering, which, because it was made from clean beasts and clean birds, represented the same as that of which it was the meaningful sign. Clean beasts represented goods that stem from charity, and clean birds the truths of faith. And when offering these, members of the Ancient Church meant that they were offering gifts of those goods or truths to the Lord. Nothing else can be offered up to the Lord that will please Him. But their descendants, like the gentiles, and also the Jews, corrupted these offerings, for they did not even know that these had such a meaning. They confined worship solely to things of an external nature.
 That the altar was the chief representative of the Lord becomes clear also from the consideration that there were altars even among gentiles before all the other religious observances were established, before the Ark [of the Covenant] was made, and before the Temple was built. This is clear from Abram's going on to the mountain east of Bethel, erecting an altar, and calling on the name of Jehovah, Genesis 12:8; from his being commanded to offer Isaac as a burnt offering on an altar, Genesis 22:2, 9, from Jacob's building an altar in Luz, which was Bethel, Genesis 35:6-7; and from Moses' building an altar at the foot of Mount Sinai and offering sacrifice, Exodus 24:4-6. Each of these events took place before the establishment of the sacrificial system and before the construction of the Ark, the place where worship was at a later time celebrated in the wilderness. The fact that gentiles too had altars is clear from what is said about Balaam telling Balak to build seven altars and to prepare seven young bulls and seven rams, Numbers 23:1-7, 15-18, 29-30, and also from the command to destroy the altars of the nations, as in Deuteronomy 7:5; Judges 2:2. Consequently Divine worship involving the use of altars and sacrifices was not something new when it was established among the Jews. Indeed men were building altars, especially those for commemorative purposes, before they ever knew of immolating young bulls and other animals on them.
 That 'altars' means a representative of the Lord, and 'burnt offerings' consequent worship of Him, is quite clear from the Prophets and also in Moses where Levi to whom the priesthood was entrusted is the subject,
They will teach Jacob Your judgements and Israel Your law. They will put incense in Your nostrils, and whole (burnt offering) upon Your altar. Deuteronomy 33:10.
This stands for the whole of worship. 'Teaching Jacob His judgements, and Israel His law' stands for internal worship, while 'putting incense in His nostrils, and whole [burnt offering] on the altar' stands for corresponding external worship, and so for the whole of worship. In Isaiah,
On that day a man will look to his Maker and his eyes will regard the Holy One of Israel. And he will not look to the altars, the work of his hands. Isaiah 17:7-8.
Here 'looking to the altars' clearly means representative worship in general, which was to be abolished. In the same prophet,
On that day there will be an altar to Jehovah in the midst of the land of Egypt, and a pillar at its border to Jehovah. Isaiah 19:19.
Here too 'altar' stands for external worship.
 In Jeremiah,
The Lord has abandoned His altar, He has abhorred His sanctuary. Lamentations 1:7.
'Altar' stands for representative worship which had become idolatrous. In Hosea,
Ephraim has multiplied altars for sinning, they have been to him altars for sinning. Hosea 8:11.
'Altars' here stands for all representative worship separated from internal, and so stands for what is idolatrous. In the same prophet,
The high places of Aven, the sin of Israel, will be destroyed. Thorn and thistle will grow up on their altars. Hosea 10:8.
Here too 'altars' stands for idolatrous worship. In Amos,
On the day I visit Israel for his transgressions, I will visit the altars of Bethel, and the horns of the altar will be cut off. Amos 3:14.
Here also 'altars' stands for representative worship that had become idolatrous.
 In David,
They will bring me to Your holy mountain, and to Your dwellings! Then I will go in to the altar of God, to God my exceeding joy. Psalms 43:3-4.
Here 'altar' clearly stands for the Lord. So the making of an altar in the Ancient and the Jewish Churches stood for a representative of the Lord. Because worship of the Lord was carried out principally by means of burnt offerings and sacrifices, and these principally meant representative worship, it is clear that the altar itself means representative worship itself.