I once worked for an oil company and one of my colleagues was a geologist whose speciality was dating rock strata by their fossil content.
he was also a fundamentalist Christian who sincerely believed the world was less than 10,000 years old. He saw no contradiction in this. His training had told him how to interpret the geological data using conventional ideas, and he did it as best he could, somehow reconciling that with his religious beliefs. In essence, he said, "I play the game by their rules and tell them what they expect to hear." Apparently, he did a good job.

When I was in high school, I was friends with a fundamentalist Christian family, particularly their teenage son. We argued continuously about evolution. Many years later, he confessed to me his father (a church deacon and Sunday School teacher) came up to him after one of our arguments and told him privately "Son, your friend Elisee IS right, you know. Darwin's theory does make sense, it's the only thing that explains the facts. Just don't tell your mother I told you this."