I actually think it's fatal for long-term Christian thinking and fatal for the long-term health of Christianity per se to live under different basic commitments in professional life and church life. To say that I adopt the rules of the game for academic life Monday to Friday, and the rules of church life on Sunday, that's a real problem.
However, what's required for many domains of learning, and I would include biblical studies, is the serious use of the mind while the spirit is fully cast in a Christian foundation. That can be a difficult challenge where much of the formal thinking about something has been dominated by non-Christian influences for some time, as would be the case in biblical study at research universities.
But the way forward is not to split the personality. The way forward would be following the path charted out by the really significant Christian philosophers of the late 20th and early 21st centuries, who have urged more professional abilities, but also more courage in letting Christian foundations dictate how those professional abilities are put to use. I am filled with admiration for people like Robert Adams, Nicholas Wolterstorff, and Alvin Plantinga, who have been thoroughly elite and thoroughly professional, but also foundationally Christian in how they put to use their professional wisdom. That, I think, is the model. They have not divided themselves into an academic part and a believer part.