The Bible and the Value of Pi
by Tim Chaffey
Critics and skeptics often claim that the Bible is in error because it says that the value of pi is 3 rather than 3.14159… Many Christians have been stumped by this claim which is based off a pair of passages found in 1 Kings 7: 23 – 26 and 2 Chronicles 4: 2 – 5. These passages describe the construction and specifications of the Bronze Sea in the temple.
1 Kings 7: 23 – 26 states:
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.
Below its brim were ornamental buds encircling it all around, ten to a cubit, all the way around the Sea. The ornamental buds were cast in two rows when it was cast. It stood on twelve oxen: three looking toward the north, three looking toward the west, three looking toward the south, and three looking toward the east; the Sea was set upon them, and all their back parts pointed inward. It was a handbreadth thick; and its brim was shaped like the brim of a cup, like a lily blossom. It contained two thousand baths.
Since the circumference of any circle can be found by multiplying its diameter by pi, the sea’s circumference should be 31.4 cubits. The Bible says “a line of thirty cubits measured its circumference.” Is this a verifiable error in the Bible as so many critics claim? Not at all. Once again, careful examination verifies the biblical account and the critic is left with egg on his face.
First of all, most apologists would say that the Bible is simply using round numbers – which of course is allowable. I'm sure when the Bible said that the Angel of the Lord killed 185,000 Assyrians in one night it was using a round number (2 Kings 19: 35). The popular evangelical apologist Norman Geisler wrote:
This is not an error. The biblical record of the various measurements of the different parts of the temple are not necessarily designed to provide precise scientific or mathematical calculations. Rather, the Scripture simply provides a reasonable approximation. The rounding of numbers or the reporting of approximate values or measurements was a common practice in ancient times when exact scientific calculations were not used.
While this is a perfectly acceptable explanation, I believe there is a better one. I do not believe the Bible is using a round number nor do I deny the plain meaning of this verse. Yes, the Bronze Sea was 10 cubits wide and five cubits high and was a hemisphere (half of a sphere) so naturally the circumference should be 31.4 cubits, right?
Well, let's take a look. As is often the case, the critics forget to read “the rest of the story.” If you read a little bit further in the text you will discover that both passages say that the Bronze Sea was a "handbreadth" thick. Any horse lover will tell you that a handbreadth is equal to four inches. So let's do some math, shall we?
1) 10 cubits = 180 inches
2) Subtract 8 inches (2 handbreadths - one on each side) to determine the diameter of the inside of the bowl. This equals 172 inches.
3) When you multiply 172 x pi you get 540.08 inches, which equals 30.004 cubits, which is within 4/1000 of what the Bible says. That’s pretty precise.
“Wait a minute!” the skeptic cries, "you can't do that because the Bible is talking about the outer circumference!" How does he know that? First of all, it gives us two important figures. The first is the diameter (10 cubits). The Israelites would need to know this figure if they wanted to move this huge bowl through an opening, such as a doorway. Second, it gives us the inner circumference so that we can figure out the volume. To find the volume of a sphere it is 4/3 x pi x r3. In this case, since it is a hemisphere, you would only need to use 2/3 instead of 4/3.This is a perfectly legitimate explanation for this account and it also shows how precise the Bible is in giving details. Once again, the Bible stands up to the critics’ attack.
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