I am new here and have been reading the posts. I am a Christian and I also believe in an old earth.
The first thing I am going to say is to look at Psalm 19:1-2
"The heavens declare the glory of God, and the sky proclaims the work of his hands.
Day after day they pour out speech; night after night they communicate knowledge."
This means that the observation of creation calls for an acknowledgement of God's existence. The wisdom and power and glory of God are displayed in what he has made. What he has made will reveal itself to us and through this knowledge we will learn about his creation. When we deny what we see because we adhere to an interpretation that causes conflict between God's word and God's creation, we are refusing to see what he is trying to teach us.
God's word is inerrant, God's creations will not mislead us, so if there's a conflict between the Bible and science the problem is not with either one of them, but with our interpretation.
I believe whoheartedly in our Lord and love him with all my heart, soul and mind. I believe that science reveals God's creation. So to attach my faith to one or the other is to close my worldview to the truth. Hundreds of years ago many people lost their faith because Galileo discovered that the earth revolves around the sun. They denied it and what did it get them. Those people lost the faith needlessly if only they would open their minds.
The Bible is inerrant but it is not a science book. You won't find answes to scientific problems there. Science books are not spiritual. They deal with findings using the scientific method. So to attach your belief on something like "evolution is a lie" or the earth is 6000 years old is really doing a disservice to God and his creation. He wants us to learn. Evolution seems to be a "cuss word" among some Christians. Why? Does it matter whether God took 6 days or 14.8 billion years to create something. I don't think so. Either way, the creation is incredible. Look at what he achieved. If you build a doll house for your daughter at the age of 4 and tell her, when she asks how you got it, I created it out of thin air. Then as she grows she realizes that was impossible, that you must have built it over a few years. Will she love you less for it? Don't think so. So what does it matter if it's a few days or billions of years. Look at what nature (science) has revealed and thank the Lord for revealing the truth to you.
I have no problems believing in the Genesis account and old earth. That does not make me a non-believer. On the contrary, it makes me love the Lord more for his painstaking creation in order that I may live. God bless you all.