Albert Barnes Commentary 1 Kings 7:23

"And he made the molten sea of ten cubits from brim to brim, round in compass, and the height thereof was five cubits; and a line of thirty cubits compassed it round about." — 1 Kings 7:23 (ASV)

Solomon's "molten sea," named for its great size, replaced the tabernacle's laver (Exodus 30:18–21), which was required for the ceremonial washings of the priests. It was ten cubits, or fully fifteen feet, in diameter at the top, making it forty-seven feet in circumference, with a depth of five cubits, or seven and a half feet.

However, a hemispherical vessel of these dimensions could not hold 2,000 baths (1 Kings 7:26), let alone the 3,000 baths mentioned elsewhere (2 Chronicles 4:3), since a bath was equal to about eight and a half gallons. To account for this volume, it is now generally supposed that the bowl bulged considerably below the brim and that it also had a "foot," or basin, which received water drawn from the main vessel through taps.

The two different measurements may be reconciled if the "2,000 baths" refers to the quantity of water ordinarily supplied to the "sea," while the "3,000 baths" indicates the absolute maximum the laver could possibly hold. While bowls of considerable size are represented in Assyrian bas-reliefs, none approach the dimensions of Solomon's. The largest vessel mentioned by the ancient Greeks held only 5,400 gallons—less than one-third of the molten sea's contents, even by the lowest estimate.