The Meaning of Numbers: The Number 40
Mentioning 146 times in Scripture, the number 40 generally symbolizes a period of testing, trial or probation. During Moses' life, he lived forty years in Egypt and forty years in the desert before God selected him to lead his people out of slavery.
Moses was also on Mount Sinai for 40 days and nights, on two separate occasions (Exodus 24:18, 34:1 - 28), receiving God's laws. He also sent spies, for forty days, to investigate the land God promised the Israelites as an inheritance (Numbers 13:25, 14:34).
The prophet Jonah powerfully warned ancient Nineveh, for forty days, that its destruction would come because of its many sins. The prophet Ezekiel laid on His right side for 40 days to symbolize Judah's sins (Ezekiel 4:6).
Elijah went 40 days without food or water at Mount Horeb. Jesus was tempted by the devil many times during the 40 complete days he fasted just before his ministry began. He also appeared to his disciples and others for 40 days after his resurrection from the dead.
The number forty can also represent a generation of man. Because of their sins after leaving Egypt, God swore that the generation of Israelites who left Egyptian bondage would not enter their inheritance in Canaan (Deuteronomy 1). The children of Israel were punished by wandering the wilderness for 40 years before a new generation was allowed to possess the Promised Land.
Jesus, just days before his crucifixion, prophesied the total destruction of Jerusalem (Matthew 24:1 - 2, Mark 13:1 - 2). Forty years after his crucifixion in 30 A.D., the mighty Roman Empire destroyed the city and burned its beloved temple to the ground.
Appearances of the number forty
The book of Exodus, with its 40 chapters and 1,213 verses, is the seventh longest book. The longest is the Psalms.
From the time they entered the Promised Land, to the time of King Saul, Israel was sporadically governed by a number of individuals known as Judges. Though they did not rule like a king, they nevertheless had a tremendous influence on the people, as they represented God and were inspired to execute his will. Judges who served 40 years include Othniel, Deborah and Barak, Eli and Gideon.
The first three human kings over the children of Israel, Saul, David and Solomon, each ruled for forty years (1050 to 930 B.C.). After the united kingdom split into two separate pieces, King Joash served forty official years (39 actual years) as one of Judah's better kings.
Abraham tried to bargain with God to not destroy Sodom and Gomorrah if forty righteous people were found (Genesis 18:29). Both Isaac and Esau were forty years old when they were first married (Genesis 25:20, 26:34).
God flooded the earth by having it rain for forty days and nights (Genesis 7:12). After the patriarch Jacob (Israel) died in Egypt, the Egyptians spent forty days embalming his body (Genesis 50:3).
Number 40 and humility
God allowed the ancient Israelites, from time to time, to be harassed and dominated by certain enemies in order to chastise and humble them for their sins. The Philistines, in the southern and western parts of Israel's land, harassed them from 1105 to 1065 B.C. God's resolution to the harassment was Samson (see Judges 13:1, 1Samuel 7:13, 15 - 17).
More info on Biblical Meaning of 40
The Bible was written by forty different people. Those called of God are now under probation, or judgment, based on how they live by every word of God.