Three: the number of the Trinity

The number three is the second most sacred number in the numeric code (behind only the number seven). Like the number one, it is associated with God, but while the number one pertains to God, the number three completes the Holy Trinity. It represents the sum of the number one (the Father) plus the number two (the Son and Holy Spirit, opposites in flesh and spirit). In addition to relating to the Holy Trinity, the number three is associated with actions of God, since such actions are manifestations of the Father working through the Son or the Holy Spirit.

The number three has a special association with Jesus. This association is appropriate to the bible's numeric code and is, in fact, one of the greatest examples of the awesome miracle the numeric code represents. After all, the sending of his only Son to earth to die for man was God's greatest act. And the many miracles performed by Jesus during his stay here are the most concentrated series of divine interventions recorded.

Jesus began his ministry at age 30 (3 + 0 = 3) and taught for three years. He faced three temptations in the desert and was in the tomb three days prior to his resurrection. The number three appears so often in relation to Jesus' life that the association cannot be random. 

Summarized from Cracking The Bible’s Numeric Code by Dr. R.J. Gannaway.