Here is a question and answer from the LCMS FAQ at lcms.org that looks at the Bible and the age of the earth.
Age of the earth
Q: What is the LCMS position regarding the age of the earth? Must we accept literally the creation account that points in the direction of a relatively young earth, given the amount of scientific evidence that concludes the earth’s age to be in the billions of years?
A: The Lutheran Church—Missouri Synod does not have an official position on the precise “age of the earth,” since the Bible itself does not tell us how old the earth is. Nor is it the Synod’s position that everything in the Bible is to be understood “literally.” There is much in the Bible that clearly purports not to be understood literally–but this must be determined by the Bible itself, not by science or human reason. There is nothing in the Bible itself to suggest that the creation account is not meant to be taken literally.
The Synod has affirmed the belief, therefore, based on Scripture’s account of creation in the book of Genesis and other clear passages of Scripture, that “God by the almighty power of His Word created all things in six days by a series of creative acts,” that “Adam and Eve were real, historical human beings, the first two people in the world,” and that “we must confess what St. Paul says in Romans 5:12” about the origin of sin through Adam as described in Genesis 3 (1967 Synodical Resolution 2-31). The Synod has also, therefore, stated that it rejects “all those world views, philosophical theories, exegetical interpretations and other hypotheses which pervert these biblical teachings and thus obscure the Gospel” (1967 Synodical Resolution 2-31).
At the same time, the Synod firmly believes that there can be no actual contradiction between genuine scientific truth and the Bible. When it comes to the issue of the age of the earth, several possibilities exist for “harmonizing” Biblical teachings with scientific studies (e.g., God created the world in an already “mature” state, so that scientific “data” leads one to the conclusion that it is older than it actually is, etc.)
Numerous books are available that discuss these issues in more detail. One of these is Studies in Creation by John Klotz (1985), available by contacting Concordia Publishing House (800-325-3040 or http://www.cph.org), and asking for stock no. 12-3004.
Usage: We urge you to contact an LCMS pastor in your area for more in-depth discussion. Published by: LCMS Church Information Center
©The Lutheran Church—Missouri Synod
1333 S. Kirkwood Road, St. Louis, MO 63122-7295 888-843-5267 • email@example.com • http://www.lcms.org/faqs