Would the REAL church please stand up – Confusion in the Kingdom of God

Churches[This is a reflection on my San Diego Reader Column where I visited a different church each week for 2005 and part of 2004.]
One theme that developed as I spoke with different pastors/priests for a variety of denominations and faiths is that each one was convicted that their expression was the true expression of faith. Catholic Priests had a sense of confidence that “theirs was the true church that traced itself back to Peter and Jesus Christ.” The Mass was the place where the Eucharist was served and followers needed to access the grace offered here. Yet, other splinter Catholic groups (Byzantine and Old Catholics) were quick to point out their legitimacy in relation to the “ROMAN Catholic” traditions.
On the other side of the world, Eastern Orthodox congregations (visited two, one Greek and the other Antiochian) were most vocal in their position as ‘truest church’. [“I believe the [Greek Orthodox Church] is the true church, but I’m not going to rub it in anyone’s face,” said Nazo Zakkak, an altar boy at St. Gregory of Nyssa Greek Orthodox Church.]
Both these groups (Catholics & Eastern Orthodox) often citied the amount of denominations in the Protestant movement as an indictment against Evangelicals. “There are 20,000 some-odd denominations, any time an Evangelic has a minor doctrinal disagreement, they just go off and start their own church,” is a common comment about Protestantism.
Where does this leave us? How do we deal with the denominational divides? One comment is often, “In essentials, unity. In non-essentials, liberty.” Yet an Orthodox Father pointed out that denominations aren’t even in agreement on what is essential or non-essential so how can their be unity. It seems like the church is in a mess but why does God allow such a divergent expression of faith amongst people who call themselves Christians?