A pillar and foundation of truth

the church of the living God, a pillar and foundation of truth (1 Tim 3:15).

This is a Catholic prooftext that I've often discussed. 

i) Did Paul consider "the church" to be infallible? Paul didn't even regard Pauline churches as infallible. Would he call the church of Corinth a "pillar and foundation of truth"? Would he call the Galatian churches "a pillar and foundation of truth"? Even churches he planted and supervised were prone to moral and doctrinal aberrations. 

ii) A Catholic apologist might object that God doesn't protect individual congregations from falling into heresy. But this means Catholic theologians must add qualifications to 1 Tim 3:15 that are conspicuously absent from the text.

iii) Over and above that, notice what Paul doesn't say. He doesn't say the papacy is a pillar and foundation of truth. He doesn't say the Roman episcopate under the Roman pontiff is the pillar and foundation of truth. He doesn't say church councils ratified by the pope constitute a pillar and foundation of truth. 

When Catholic apologists read this verse, they mentally substitute something it doesn't say in place of what it actually says.

In this verse there's no lay/clerical dichotomy. No doubt Paul thought pastors should be guardians of doctrinal truth, but he doesn't drive a wedge between pastors and laymen in that regard. 

Most of his letters are addressed to the entire congregation. To be read aloud in church. Christians in general are supposed to uphold the Gospel truth. It's not as if he thinks pastors are supposed to safeguard the truth while laymen are not supposed to safeguard the truth. When Paul says "the church" in 1 Tim 3:15, he's not excluding the congregation, as if elders and deacons are the church, but the congregation is not. As a Catholic prooftext, this verse either proves too much or too little.