Many faithful nurses practice with scientific knowledge. So from a nursing perspective, even the most religious of nurses need to know their science.
Cultural and spiritual needs of the patient should be addressed nonjudgmentally by the nurse. The nurse should however, not practice his/her religion, unless the patient asks for it. For instance if a nurse and a patient are of the same faith, and the patient asks, and the nurse is comfortable then a nurse can pray with and for a patient. Most hospitals also have Chaplin services. Also, the Christian faith has many hospitals, from Methodists, the Catholic (on of the largest and best hospitals in this area, a major trauma center, is Catholic), and Seventh Day Adventists (one of the largest hospitals in Orlando, and one of the best), to Baptist in my area alone.
So whether or not we philosophically (sp?) think religion and medicine should mix, the reality I think is that it does, presuming that medicine and nursing are science based.
I hope this makes sense, as I'm tired, and I'm sorry for any typos.