The number 40

Testing, trial, probation, preparation

Testing and judgment: seasons of trial

Forty is scripture's clearest number of testing, and Bullinger's Number in Scripture gives it a full chapter, more space than almost any other number in the book. Its great spans: forty years of Israel's wilderness probation (Deuteronomy 8:2-5; Psalm 95:10; Acts 13:18), forty days of rain in the flood (Genesis 7:12), forty days Moses on Sinai receiving the law (Exodus 24:18; 34:28), forty days the spies scouted Canaan, answered by forty years of wandering, a year for each day (Numbers 13:25; 14:34), forty days Elijah walked to Horeb on one meal's strength (1 Kings 19:8), forty days Nineveh was given to repent (Jonah 3:4), forty days Jesus fasted and was tempted (Matthew 4:2), and forty days the risen Christ appeared before his ascension (Acts 1:3). Bullinger reads it as 5 x 8, grace leading to renewal, and calls it probation and chastisement of a covenant people, never judgment of enemies. The existing label matches this closely; no honesty flag needed.

The mathematics

40 = 2³ × 5, the fourth octagonal number.
Forty's weight is not in its arithmetic but in its seasons: forty days of rain, forty years in the wilderness, forty days of fasting, and the forty days between the resurrection and the ascension.

Every property here was checked before it was printed.

The same number, in what He made

A child is carried forty weeks. Obstetrics dates every birth at 280 days — forty weeks — from the beginning of the cycle that conceived it (ACOG Committee Opinion No. 700, 2017).

So the number Scripture spends on testing is the same number a body spends on forming a child. Forty is not only the wilderness; it is also the womb — the same span, measured in waiting.

Sources are named in the line itself. “The heavens declare the glory of God; and the firmament sheweth his handywork.”

What they have said about this number

Probation, trial and chastisement — the discipline of sons, distinct from judgment.

“The uniformity of its association with a period of probation, trial, and chastisement — not judgment, like the number 9… but the chastisement of sons, and of a covenant people.”

E. W. Bullinger, Number in Scripture (1894)

“Seasons of testing and transformation — crucible periods for leaders and nations.”

Troy Brewer, Numbers That Preach (2007)

In Hebrew and Greek

Hebrew

Arbaim (אַרְבָּעִים) - forty

Greek

Tessarakonta (τεσσαράκοντα) - forty

First occurrence

Genesis 5:13

And Cainan lived after he begat Mahalaleel eight hundred and forty years, and begat sons and daughters:

The pattern in Scripture

40 days of flood (Gen 7:17)
Moses on Sinai 40 days (Exod 24:18)
Israel in wilderness 40 years (Num 14:33)
Jesus tempted 40 days (Matt 4:2)
40 days before ascension (Acts 1:3)
Eli judged 40 years
Saul, David, Solomon each reigned 40 years

Key verses

Genesis 5:13

And Cainan lived after he begat Mahalaleel eight hundred and forty years, and begat sons and daughte...

Genesis 7:4

For yet seven days, and I will cause it to rain upon the earth forty days and forty nights; and ever...

Genesis 7:12

And the rain was upon the earth forty days and forty nights.

Genesis 7:17

And the flood was forty days upon the earth; and the waters increased, and bare up the ark, and it w...

Genesis 8:6

And it came to pass at the end of forty days, that Noah opened the window of the ark which he had ma...

40:40 verses

Ezekiel 40:40

And at the side without, as one goeth up to the entry of the north gate, were two tables; and on the...