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. (ASV)
I will grant the arguments given in the Con and Neutral sections of this entry would be convincing were it not for one fact. In the pre-Islamic Era, before the creation of the concept of zero and decimal fractions, all mathematics were integer mathematics.
Unfortunately for the author of the Pro section, the error (pi=3) persists even in an all-integer mathematical regime because the measured circumference of a ten cubit vessel would be given as 31 cubits. Likewise, I can't see the authors of the Masoretic texts using approximate measurements to describe one of the most sacred items in their religion (a large vessel used in Solomon's Temple).
In short, this is an error of fact.
The dimensions of the molten sea are provided in two places in the Bible.
“And he made the Sea of cast bronze, ten cubits from one brim to the other; it was completely round. Its height was five cubits, and a line of thirty cubits measured its circumference…It was a handbreadth thick; and its brim was shaped like the brim of a cup, like a lily blossom.” (1 Kings 7:23,26)
Then he made the Sea of cast bronze, ten cubits from one brim to the other; it was completely round. Its height was five cubits, and a line of thirty cubits measured its circumference…It was a handbreadth thick; and its brim was shaped like the brim of a cup, like a lily blossom. (2 Chronicles 4:2,5)
Both sources agree on the dimensions of the molten sea.
1. It was ten cubits from one brim to the other.
2. A line of thirty cubits measured its circumference
3. It was a handbreadth thick.
4. Its height was five cubits.
Ten cubits measures the diameter from brim to brim or the outside on the sea. The brim was shaped like a lily blossom so the top would curve outward all around. The circumference of the outside of the sea along the brim is 10 x Pi = 31.4 cubits.
A line of thirty cubits measured its circumference. This is the inside measurement below the point where the brim curves outward. The inside diameter of sea is 30 / Pi = 9.55 cubits
The sea was a handbreadth thick. We are not told the measurement of a handbreadth in cubits so it does not matter. It would not be more than 10 – 9.55 = 0.45 cubits or not more than 8-9 inches based on an 18 inch cubit. Any person can use his own hand to measure this and make the sea as thick as his hand. The handbreadth would then determine the outward curvature of the brim.
To see a picture of the molten sea and the dimensions plus a more detailed description, go here— 
Given the above information, anyone can build an exact replica of the molten sea.
There is no conflict with the measurement of Pi in the calculations.
Someone has said that this verse contains a mathematical error, since it says that the diameter is 10 and the circumference is 30, implying that pi=3.
But either the measurements were exact, or they were approximate.
If they were exact, then certainly the diameter and circumference should reveal the pi relation. If they were approximate, then this is not an issue.
I noticed in verses 24-26, it says there is a graven work under the brim, and that the brim was like the leaf of a crisped lilly. Could that mean there was an overhanging ledge?
I did some calulations, and find that if the brim overhung the ledge by about 4.1 inches (assuming 1 cubit=18 inches), then the numbers work out, since the diameter of the portion below the rim would then be less than 10 cubits. For a pool that is 15 feet in diameter, a ledge that wide makes sense.
But this is just one possibility. The point is that no error, no deception, and no fraud is involved in Holy Scriptures.
The above last paragraph is pointless. If someone seriously believes that, then why bother with any other discussion, or even go to an errancy webpage? -Equinox 7.27.06
Actually, this verse doesn't mention or even imply the PI at all. It only states two measurements, the circumference and the diameter. As far as the writer and the readers are concerned, there might or might not be such an entity as a PI; that is not even a side issue in the text. If we decide to call the relation of the circumference to the diameter a PI (as geometricians have done), that is one thing, but we can't reasonably expect to get an accurate value for PI in this kind of a text.