Numbers Three and Four Together
The Bible sometimes uses numbers to represent something other than a mathematical value. A perfect example of this principle is found in Proverbs 30. This chapter, written by a man named Agur (verse 1), utilizes the number three (x) to accentuate the meaning of four (x + 1).
The pattern in chapter 30 of Proverbs occurs in four sets of verses (verses 15 to 16, 18 to 19, 21 to 23 and 29 to 31). The first two of these sets contain two verses while the last two contain three verses. Each number coupling is followed by a list enumerating four examples of what is being discussed.
Four Unlimited Things
Three things are never satisfied, yea, four things never say, 'Enough!'
The grave, the barren womb, the earth not filled with water, and the fire have never said, 'Enough.' (Proverbs 30:15 - 16).
Verse 16 of Proverbs 30 lists four things Agur discovered had no limits. These were death, wombs unable to produce children, the parched earth always in need of water and fire which will consume everything it can.
Four Amazing Abilities
Three things which are too wonderful for me, yea, four which I do not understand:
the way of an eagle in the air; the way of a snake on a rock; the way of a ship in the middle of the sea; and the way of a man with a maiden (Proverbs 30:18 - 19).

Agur now lists four things that amazed him and caused him to wonder. The first three are how an eagle flies, how a snake transports itself on the ground, and how a heavy ship can maneuver and float in water. The fourth behavior that baffled him was how a man courted a woman to marry.
Four Intolerable Events
For three things the earth is disquieted, and for four it is not able to bear up:
for a slave when he reigns; and a fool when he is filled with food; for a hateful woman when she is married; and a servant girl that is heir to her mistress (Proverbs 30:21 - 23).
Agur then lists four things that are inappropriate and unbearable for humans to tolerate. The first two are when a servant becomes a ruler as he is ill equipped for the job and a fool who, after his needs are met, pursues obnoxious behavior against all others.
The two other things humans cannot stand are contentious women with vicious habits and a servant who through guile will inherit the wealth of her master.
Four Noble Behaviors
There are three things which go well, yea, four that go stately in walking:
A lion is mighty among beasts and does not turn away for any; A greyhound, a male goat also, and a king, against whom there is no rising up (Proverbs 30:29 - 31).
The last of the number pairings of three and four in Proverbs are things which seem majestic and stately. The first is a lion, as it is the king of beasts. It is unknown, however, which animal is the first one referenced in verse 31. While the King James and HBFV call it a greyhound, the NIV and other translations label it a strutting rooster while The Living Bible calls it peacock!
The third thing that appears majestic is a he-goat when it leads the flock. The last of the four noble things is a king whose power no one is willing to challenge.