The Catholic Church Fathers believed that the numbers in the Old Testament had mystical meaning, but they warned against going too far with mystical conceptions.
The Catholic Church has long held that certain numbers have significance, but this belief rejects the structured divination related to numerology.
According to the Catholic Church, numbers clearly have notable significance in the Old Testament.
For example, the number seven represents completion and rest, as God rested on the seventh day of creation. When a promise is kept, the number 40 is frequently used. This was true during the Noahic Flood when it rained for 40 days in a row and Israelis lived on Manna for 40 years.
St. Anselm explains why the number seven is good, but not in the way that Pythagoras and other philosophers do, but rather in terms of the manifestation and division of the Spirit’s grace.