Ronald Reagan did not attend church outside of the WH after the assassination attempt. BUT, he and Nancy invited pastors to conduct private services INSIDE the WH. Reagan was criticized for that, but he said that he did not want to disrupt the church experience for other parishioners attending.
OTOH, George W. Bush attended church frequently and quietly -- even slipping into daily services at a church near the WH.
The fact that congress has not been allowed to break for Christmas, shows the lack of respect for Christianity.