By: Gen. Jim – 9/18/25
(1) Great Flood/Noah
We might ask ourselves why the Bible uses the number 40 so many times when describing extraordinary/historical events?
Take Genesis 7:4 “For yet seven days, and I will cause it to rain upon the earth forty days and forty nights; and every living substance that I have made will I destroy from off the face of the earth.” Genesis 7:12 “And the rain was upon the earth forty days and forty nights.” And Genesis 7:17: “Now the flood was on the earth 40 days. The waters increased & lifted up the ark, & it rose high above the earth.” – Before this, the LORD said to Noah, “… I will cause it to rain on the earth 40 days & 40 nights, & I will destroy from the face of the earth all living things that I have made,” vs. 4. Then the Bible says, “And it came to pass at the end of 40 days, that Noah opened the window of the ark which he had made,” 8:6.
We know the reason for the Great Flood: “And God saw that the wickedness of man was great in the earth, & that every imagination of the thoughts of his heart was only evil continually,” 6:5.
The Hebrew word for “imagination” is yēçer or yêtser, meaning “conception” (i.e., purposed to do evil). Although it is used with this meaning in only 5 other places in the O.T. (e.g., Dt. 31:21; 1 Chron. 28:9; 29:18; Isa. 26:3; Gen. 8:21), this word came to be of extraordinary significance in Jewish thought and usage. It is used in Ecclesiaticus 15:14, “He [God] Himself made man from the beginning, & left him in the hand of his counsel [yēçer].” This verse is part of Ben Sirach’s explanation of the presence of “moral evil” in the world. Its origin is within man/woman – a thought to which the author gives further sardonic expression in Ecclesiasticus 21:27,“When the ungodly curseth Satan, he curseth his own soul.”
Think about this. Sin is the result of man’s fixing his/her imagination on themselves, or on some other thing or person other than their creator. I love what Isaiah says in 26:3: “Thou wilt keep him in perfect peace [i.e., unharmed, or in welfare], whose mind [yēçer] is stayed on thee; because he trusteth in Thee.” [note: in rabbinical lit. yēçer is used with the meaning of “impulse”, the good or evil “tendency” in man/woman.].
(2) Isaac
“Isaac was 40 years old when he took Rebekah as wife…” -Gen. 25:20
(3) Esau
“When Esau was 40 years old, he took us wives Judith… & Basemath…” -Gen. 26:34
(4) Joseph & Jacob
“And Joseph commanded his servants… to embalm his father (Jacob)… 40 days were required for him…” -Gen. 50:2, 3
(5) Israel
“And the children of Israel ate Manna 40 years…” -Ex. 16:35
(6) Moses
“So, Moses went into the midst of the cloud & went up into the mountain. And Moses was on the mountain 40 days & 40 nights,” -Ex. 24:18
(7) The Tabernacle
“You shall make 40 sockets of silver…” -Ex. 26:19, 21
(8) Spies
“And they returned from spying out the land after 40 days,” -Num. 13:25
(9) Disobedient Israel
“And your sons shall be… in the wilderness 40 years…” -Num. 14:33, 34; 32:13; Dt. 2:7; 8:2, 4
(10) Punishment
“40 blows he may give him & no more…” -Dt. 25:3
(11) Joshua
“I was 40 years old when Moses… sent me…” -Jos. 14:7
(12) Land Had Rest
“So the land had rest for 40 years…” -Judg. 3:11
(13) Disobedience Again
“Again the children of Israel did evil in the sight of the LORD, & the LORD delivered them into the hand of the Philistines for 40 years.” -Judg. 13:1
(14) Eli
“And the Philistines drew near & presented himself 40 days, morning & evening,” -1 Sam. 17:16
(16) Absalom
“Now it came to pass after 40 years that Absalom said to the king…” -2 Sam. 15:7. [note: the O.T. Greek, aka LXX, the Syriac Mss., Josephus has 4].
(17) David
“The period that David reigned over Israel was 40 years…”, 1 Kgs. 2:11
(18) Solomon
“Solomon had 40,000 thousand stalls of horses…” -1 Kgs. 4:26; “The period that Solomon reigned in Jerusalem over all Israel was 40 years.” -1 Kgs. 11:42
(19) Jehoash
“… Jehoash became king, & he reigned 40 years in Jerusalem…” -2 Kgs. 12:1 (Jehoash is also known as Joash 2 Kgs. 11:2).
(20) Asher
“Of Asher, those who could go out to war, able to keep battle formation, 40,000.” -1 Chron. 12:36; (see also 19:18).
(21) Israel/God
“For 40 years I (God) was grieved with that generation…” -Ps. 95:10
(22) Ezekiel
“… you shall bear the iniquity of the house of Judah 40 days…” -Ez. 4:6
(23) Egypt
“Neither foot of man shall pass through it (Egypt), & it shall be uninhabited 40 years.” -Ezek. 29:11
(24) Jesus
“And when He had fasted 40 days & 40 nights…” -Mt. 4:2 (see also Mk. 1:13; Lk. 4:2)
(26) Jesus
“… He also presented Himself alive after His suffering… being seen by them during 40 days…” -Acts 1:3
(27) Moses
“And Moses… was mighty in words & deeds. Now when he was 40 years old, it came into his heart to visit his brethren…” -Acts 7:22, 23. (see also vs. 30 & vss. 36 & 42)
(28) Soul
“… they asked for a king; so God gave them Saul… for 40 years.” -Acts 13:21
Why 40?
There are 2 Heb. words that describe the number 40:
1) ‘arbâ’îym = multiple of ‘arba’ = 4, from râba’ = to be quadrate (4);
2) ribbôw = a myriad (40,000 etc.), from râbab = multiply, 10,000;
There are also 2 Gk. words:
1) tessarakonta = 40;
2) tessarakontaetēs = 40.
Tessarakonta is used in circumstances in Scripture which indicate the number as suggesting probation, separation or judgment, e.g., Mt. 4:2, when Jesus fasted 40 days/nights; Acts 1:3,when Jesus presented Himself alive to His followers for 40 days; Heb. 3:9, when Israel tested God & saw His works 40 years; vs. 17, with whom God was angry 40 years.
[note: Tessarakontaetēs, 40 years (etos = a year), is found in Acts 7:23, concerning Moses; Acts 13:18, when God had put up with Israel’s rebellious ways in the wilderness].
The Number 4
Tessares, 4/four, is not found in the N.T. outside the Gospels, the Acts & Apocalypse; in the last it is very freqent. Tetartos, fourth, is found in Mt. 14:25; Mk. 6:48 & 7 times in the Apocalypse; also in Acts 10:30, “four days ago”, lit., ‘from a fourth day’. Dakatessares, fourteen (14) = ten-four, is found in Mt. 1:17; 2 Cor. 12:2; Gal. 2:1 –
Tessareskaidekatos, fourteenth (lit., 4-&-tenth), Acts 27:27, 33; tetrakosia, = 400, Acts 5:36; 7:6; 13:20; Gal. 3:17. In Acts 7:6 the 400 years refers to Abraham’s descendants & to the sojourning & the bondage. This agrees with Gen. 15:13. In Ex. 12:40 the 430 years dates from the call of Abraham himself. Likewise the giving of God’s Law was 430 years from the Promise in Gen. 12:3, which agrees with Gal. 3:17. In john 11:39 (Gk.) tetartaios, lit., ‘a fourth day (one)’, is rendered “four days”.
Fourfold = tetraploos (Lk. 19:18);
Fourscore = Ogdoēkonta (Lk. 2:37; 16:7);
Foursquare = tetragōnos (Rev. 21:16).
[Note: Both Moses & Jesus fasted 40 days & 40 nights: Ex. 34:28 – Moses, Mt. 4:2 – Jesus]
Concerning the Great Flood – Gen. 7:12: “And rain fell on the earth 40 days & 40 nights”: Another instance of crucial 40-day period include Noah’s waiting 40 days following the Great Flood to send out a raven (8:6).