When the Bible speaks to an issue, it is the supreme authority. Thus, what the Bible has to say about the age of the Earth carries great significance. The Bible never specifies a date for creation, but the creation accounts in Genesis provide some guidance. The genealogies and the length of the creation days play key roles in any biblical assessment of Earth’s age. The genealogies place a hard constraint that Adam and Eve appeared no more recently than 6,000 years ago. Since those genealogies contain gaps, they cannot serve as timekeeping devices. However, it seems to stretch credulity to argue for anything much older than 100,000 years for Adam and Eve’s appearance on Earth.
Any other information on the Earth’s age must be inferred from the length of the creation days. The biblical word for day, yom, has four different literal meanings: 1) the daylight portion of a day, 2) part of the daylight hours, 3) an ordinary day (now 24 hours), and 4) a longer but finite period of time (no other word in biblical Hebrew carries this meaning). Although many Christians argue that those days represent ordinary calendar days, the biblical text indicates they lasted much longer. Days 1-3 cannot be ordinary days as humanity defines them because the Sun does not become visible until the fourth day. On the sixth day, Adam tends the garden, names all the animals, undergoes divine surgery, and marries Eve. These events seem too significant and long to happen in one ordinary day. The seventh day, in contrast to the first six, never closes with an evening and morning. In fact, Psalm 95 and Hebrews 4 indicate that we still live in the seventh day.
The Bible never declares an age for the Earth, but evidence derived from the text fits most comfortably with a date far older than a few thousand years. RTB holds the position that the six days of creation represent long time periods and that the creation accounts reconcile well with the scientific date for Earth’s formation 4.6 billion years ago.