The Chaldean Patriarch of Baghdad, Cardinal Louis Raphael Sako. As churches around the world gather to celebrate the annual Week of Prayer for Christian Unity, from January 18 to 25, Patriarch Louis Raphael Sako reminded the faithful that unity is not about merging churches into a single entity, but rather about embracing diversity and working together despite differences. Unity is a spiritual and practical endeavor rooted in shared faith and mutual respect, the head of the Chaldean Catholic Church in Iraq said in a pastoral statement.