What's the significance that Goliath defied Israel for forty days?

Question

1 Samuel 17:

16For forty days the Philistine came forward every morning and evening and took his stand.

22David left his things with the keeper of supplies, ran to the battle lines and asked his brothers how they were. 23As he was talking with them, Goliath, the Philistine champion from Gath, stepped out from his lines and shouted his usual defiance, and David heard it. 24Whenever the Israelites saw the man, they all fled from him in great fear.

32David said to Saul, “Let no one lose heart on account of this Philistine; your servant will go and fight him.”

After 40 days of insults, finally, David arrived at the scene to take on Goliath. Was it a literal 40 days? Is there a significance of the number, 40?

Answer 1

There is little question that a number of significant events occurred over a period of "forty days" such as:

• Gen 7:4, 12, 17 - forty days of rain at Noah's flood
• Gen 8:6 - forty days before Noah open the window of the Ark
• Gen 50:3 - forty days to embalm the body of Joseph
• Ex 24:18, 34:28, Deut 9:11, 25, 18, 10:10 - Moses was in the mountain forty days
• Num 13:25, 14:34 - the spies explored the promised land forty days
• 1 Sam 17:16 - forty days Goliath defied Israel
• 1 Kings 19:8 - Elijah traveled forty days into the desert
• Eze 4:6 - Ezekiel had to lie on one side forty days
• Jonah 3:4 - Jonah predicted the destruction of Nineveh in forty days
• Matt 4:1, Mark 1:13, Luke 4:1, 2 - Jesus was in the Desert fasting for forty days
• Acts 1:3 - Jesus appeared to His disciples after the resurrection over a forty day period

In some of these cases, these forty day periods corresponded to forty year periods as well.

(Note: our English word, "quarrantine" means literally, "forty [days]" from the Renaissance Italian.)

All that can be said about this repeated use of the "forty-day" period is its clear significance - any such period occurs at a time of great trial followed by victory. Indeed, Ellicott suggests this in his comments on Gen 7:4 -

(4) Forty days.—Henceforward forty became the sacred number of trial and patience, and, besides the obvious places in the Old Testament, it was the duration both of our Lord’s fast in the wilderness and of His sojourn on earth after the Resurrection.

The Pulpit commentary reaches a similar conclusion -

Gen 7:4 ... The importance assigned in subsequent Scripture to the number forty, probably from the circumstance here recorded, is too obvious to be overlooked. Israel wandered forty years in the wilderness (Numbers 14:33). The scouts remained forty days in Canaan (Numbers 13:26). Moses was forty days in the mount (Exodus 24:18). Elijah fasted forty days and forty nights in the wilderness of Beersheba (1 Kings 19:8). A respite of forty days was given to the Ninevites (Jonah 3:4). Christ fasted forty days before the temptation (Matthew 4:2), and sojourned forty, days on earth after his resurrection (Acts 1:3). It thus appears to have been regarded as symbolical of a period of trial, ending in victory to the good and in ruin to the evil. ...