From a philosophical point of view, he could read both Buddhist and Christian books. Religious books were usually written based on beliefs and philosophical thinking, so reading religious books would not affect one's belief and understanding of the main religion. When reading religious books, one could try to integrate the ideas of different religions to understand the essence and meaning of religion more comprehensively. In addition, reading religious books could also help develop one's philosophical thinking skills and help one better understand human culture and history. However, please note that when reading religious books, you should maintain rational and critical thinking to avoid blind faith and excessive worship. At the same time, they had to protect their privacy and respect the views of different faiths.