Why Churches of Christ?

I was asked by a Catholic with this question:

In the Romans 16:16 it was mentioned "churches of christ". Does it mean that there are lots of churches of christ?

Actually, what was referred to when mentioned "churches of Christ" was the members of the church. The members were called "churches of Christ" because the church of which they were members was the Church of Christ.

For example: why are we calling some Christians as Catholics? Well, it's because they are member of the Roman Catholic church.

Catholic Church because the Faith is Universal

My Catholic Friend attempted to prove that the Catholic Church is the church founded by Christ by simply telling me that Apostle Paul mentioned in the book of Romans that the Faith of Roman Christian is universal.

However, I told him that it couldn't be used as proof because of some reasons:

1. The letter of Paul to the Romans is not for all people in Rome but for the members of the Church of Christ in Rome.
2. Apostle Paul is not an Apostle of the Roman Catholic Church, but an apostle in the Church of Christ.
3. The faith mentioned by Apostle Paul is not the faith of the Roman Catholic Church but of the Church of Christ.

And we should also not forget that Christ built only his own Church or the Church of Christ. He didn't build any churches, especially the Roman Catholic Church, except his own Church.

Church of Christ, not Roman Catholic Church

Catholics argued that the one built by Christ is the Roman Catholic Church not the Iglesia ni Cristo because the Iglesia ni Cristo emerged only on 1914 in the Philippines while the Roman Catholic Church existed already before other church started to exist.

These people simply are confused about the Iglesia ni Cristo. Iglesia ni Cristo is a Filipino term for "Church of Christ". And just like what I wrote in my previous post, the Church of Christ that emerged in the Philippines in 1914 is one and the 3rd group among the 3 groups of members of the Church of Christ.

If you'll examine the Bible, Christ in Matt 16:18 mentioned that He would built His own Church. Remember, the church that Christ would built is His own Church not the Roman Church. Christ call this church His Church and Apostles call it Church of Christ.