Science and Pi in the Bible

Today is Pi Day!

Introduction
An axiom I have found to be true is: If your reading of the Bible leads you to contradict math or science, then it is probably your interpretation that is in error, not necessarily the Bible. First check your interpretation against other interpretations of the same passage in question. This is best illustrated in a claim I have seen a rise in lately, that the Bible misstates the value of pi (π) and therefore cannot be the Word of God.

One source presents it succinctly:
Myth: The Bible says that the circumference of a circle is exactly three times its diameter, but the correct value is pi (π), or about 3.1416.
Fact: The measurements of “the Sea of cast metal” given at 1 Kings 7:23 and 2 Chronicles 4:2 indicate that it had a diameter of 10 cubits and that “it took a measuring line 30 cubits long to encircle it.” These dimensions might have been merely the nearest round numbers.^[1]

Another source reported:
At 1 Kings 7:23 and 2 Chronicles 4:2 we are told that the circular molten sea in the courtyard of Solomon’s temple was ten cubits from brim to brim and that “it took a line of thirty cubits to circle all around it.” Is this not incorrect, since it is impossible to have a circle with these two values?

Today, in mathematical calculations, it is customary to use pi, which denotes the ratio of the circumference of a circle to its diameter. According to general practice, it is a quantity equivalent to 3.1416. However, in ancient times persons did not give decimals down to the last fraction. For that matter, pi itself is not just 3.1416. Persons who insist on scrupulous accuracy and consider the Bible to be in error in giving the measurements of the molten sea would do well to realize that, to be more accurate themselves, it would be appropriate to carry pi to at least eight decimal places, which would be 3.14159265, though even a figure in excess of 3.1415926535 could be used.

Bible commentator Christopher Wordsworth quotes a certain Rennie, who made this interesting observation regarding the measurements of the molten sea: “Up to the time of Archimedes [third century B.C.E.], the circumference of a circle was always measured in straight lines by the radius; and Hiram would naturally describe the sea as thirty cubits round, measuring it, as was then invariably the practice, by its radius, or semidiameter, of five cubits, which being applied six times round the perimeter, or ‘brim,’ would give the thirty cubits stated. [See figure below.] There was evidently no intention in the passage but to give the dimensions of the Sea, in the usual language that every one would understand, measuring the circumference in the way in which all skilled workers, like Hiram, did measure circles at that time. He, of course, must however have known perfectly well, that as the polygonal hexagon thus inscribed by the radius was thirty cubits, the actual curved circumference would be somewhat more.”

According to 1 Kings 7:23 and 2 Chronicles 4:2, the molten sea was ten cubits, or fifteen feet, in diameter and it took a line of thirty cubits, or forty-five feet, to encompass it. That is a ratio of one to three, which, for practical purposes, was quite adequate for the sake of a record.^[2]

Lastly, the Encyclopedia of Bible Difficulties similarly says:

First Kings 7:23 says, “He [Hiram] made the sea of cast metal ten cubits from brim to brim, circular in form, and its height was five cubits, and thirty cubits in circumference” (NASB). Some critics have urged this approximate value of three to one as the relationship between the diameter and the circumference of the circle amounts to a geometrical inaccuracy, inconsistent with a truly errorless Scripture. The true value of pi is calculated to be 3.14159 rather than 3.0.

This criticism is, however, devoid of merit. While it is true that the more exact calculation of pi is essential for scientific purposes, or for the manufacture of precision parts in a factory, the use of approximate proportions or totals is a familiar practice in normal speech, even today. If the statistical statements concerning the population of cities or nations were subjected to the same stringent standard as that leveled at 1 Kings 7:23, then we would have to say that all population statistics are in error. A certain number of people are dying each minute, and babies are being born at a standard rate every sixty seconds; therefore any exact sum that might be true at 1:00 P.M. on a given day through computer calculation would be “inaccurate” by 1:01 P.M. that same day. It is perfectly proper to speak of the circumference of any circle as being three times its diameter if we are speaking approximately, just as one may legitimately state that the population of China is from 800 million to one billion. The Hebrew author here is obviously speaking in the approximate way that is normal practice even today.

There is one interesting feature about this that might well be added. If the rod used to mark out a length of five cubits (approximately ninety inches) for the radius were used to measure the inside circumference of the same bowl-shaped vessel here described, then it would take exactly six of those five-cubit measures to complete the circumference. [See figure above.] Let the skeptic try it and see!^[3]

Conclusion
The axiom has proved true that the Bible is not contradicting math, but the interpretation that it was teaching a mathematical inaccuracy is what is in error. All it was referring to at the very least was how the ancients constructed a circular object. Lastly, as they did not need the level of precision we now have for pi, demanding that God reveal that to them is really quite unreasonable and therefore absurd.

Footnotes:
^[1] Does Science Agree With the Bible? Are there scientific errors in the Bible? jw.org/en/bible-teachings/questions/science-and-the-bible
^[2] w66 5/15 Questions From Readers p. 319. wol.jw.org/en/wol/d/r1/lp-e/1966367 Figure added by me.
^[3] Gleason Archer. Zondervan, 1982. 198-199.