Firstly, let me emphasize that I am not speaking of occult numerology in which Satan, the great counterfeiter, took the natural and heavenly meaning of numbers and perverted them.
Here is a simple review of some numbers and their Biblical meaning:
One unity. God is unity.
Two duality, difference, division. Good and evil represent the division of our world.
Three spiritual perfection. As the Father, Son and Holy Spirit.
Four the created world. Spiritual perfection plus one, the Creation of God. Examples are the four directions of the compass, north, south, east and west; the four seasons, spring, summer, autumn, winter.
Five is said to be the number of Grace. An example is found in First Peter 1:1-2. Peter addresses his letter to saints in five countries and then says, Grace and peace be yours. There were five porches at the Pool of Bethesda where, in John chapter five, we find people went to be healed, and Jesus healed the invalid. Healing by the Lord certainly is Grace.
Six the number of man and mans wickedness. Man was created on the sixth day. The number of the final evil man is 666. The Children of Israel lusted after six things they left behind in Egypt. (Number 11:4-5)
Seven the number of Completion. There are seven notes in a complete musical scale. There are seven colors in the rainbow.
Eight the number of new beginnings. If seven is completeness, eight starts over again. There were eight souls on the Ark to repopulate the world after the Great Flood.
Nine the number of Spiritual Completeness Paul lists nine fruits of the spirit. (Galatians 5:22-23) He again lists nine gifts of the spirit in First Corinthians 12:8-10.
Ten is said to be the number of testimony. Ten families are required to start a synagogue. The ten virgins of Matthew 25 were the required number of witnesses for a wedding.
Of course, there are many more numbers and uncountable combinations. I would like to point out one more number thirteen. Thirteen in the Old Testament is the number of rebellion. The kings of Sodom and the surrounding area rebelled against their foreign overlords in the thirteenth year. (Genesis 14:4)
There are two books that I possess that were written by Christian brothers. They are a fascinating review of usage of numbers in Scripture.