Pot
Pots" and other large vessels in the Bible represent facts and factual ideas, which serve as containers for truth the same way pots serve as containers for water or wine. Pots fill their function because they are hard, strong and impervious; facts are also absolute and unchanging, filling their function the same way. And pots must be filled to serve any use, just as facts must be filled with truth to serve any purpose. To some extent this meaning also applies to cups, bowls and other smaller vessels, though it is a little more immediate. Generally you don't fill a cup so you can store a liquid; you fill it to drink it. Smaller vessels then often take more of their meaning from the substance they contain, and in many cases ("cup" and "wine" especially) actually mean the same thing.
Apocalypse Explained # 432
432. Verse 5. Of the tribe of Judah twelve thousand sealed; of the tribe of Reuben twelve thousand sealed; of the tribe of Gad twelve thousand sealed.
5. "Of the tribe of Judah twelve thousand sealed," signifies love to the Lord, and that all who are in that love are in heaven, and come into heaven n. 433; "of the tribe of Reuben twelve thousand sealed," signifies the light of truth from that good, and that all who are in that light are in heaven and come into heaven n. 434; "of the tribe of Gad twelve thousand sealed," signifies the consequent good of life (n. 435, 436).