The belief that the world and the physical universe are only a few thousand years old rises out of an attempt to count the genealogies in the Old Testament. The seventeenth-century Anglican Archbishop James Ussher is the most famous one who said the world was created in the year 4004 B.C. on Saturday night, October 23 (Annals of the World, 9).
The problem with this approach is that genealogies were not meant to be exact chronicles of history. Often ancient authors omitted generations for the sake of symbolism. For example, Matthew records three sets of fourteen generations in his account of Jesus’ genealogy. Bible scholars point out that fourteen is the numerical value of David’s name in Hebrew (D = 4, V= 6, D= 4). The three sets of fourteen, they conclude, could possibly be Matthew’s way of emphasizing that Jesus is the new David, or it may be simply a mnemonic tool (14 to David, 14 from David to deportation into captivity, and 14 to Jesus). Moreover, as Trent Horn explains in his book Hard Sayings (see chapters 5 and 11), the ages listed in the Old Testament may not be literal but symbolic.
The purpose of the genealogies in the Bible was not to show how old everyone was but to illustrate how people were related. Bishop Ussher’s counting of the age of the universe is not definitive Catholic teaching. In fact, the Catholic Church does not have a position on a particular age of the Earth or the physical universe. This is a matter about which Catholics can legitimately disagree.
The Catechism of the Catholic Church states that the findings of modern science
. . . have splendidly enriched our knowledge of the age and dimensions of the cosmos, the development of life-forms and the appearance of man. These discoveries invite us to even greater admiration for the greatness of the Creator, prompting us to give him thanks for all his works and for the understanding and wisdom he gives to scholars and researchers (283).