Let me share with you what I believe about that Scripture. It’s not giving carte blanche final authority to the church (whatever you or I deem that to be). Break it down. What’s a pillar and ground? Something that supports something and something that is a foundation for something. So the church is the pillar and ground of what? The truth. Let’s find out what the truth is:
John 17:17 Sanctify them through thy truth: thy word is truth.
According to Jesus, the truth is the word of God: the Scriptures. So the church is to be the pillar and ground of the Scriptures. If a church is NOT upholding the word of God and is not grounded in it, can it then rightly be called the pillar and ground of truth? The authority of the church is the Scriptures. If any church departs from the Scriptures, it stands to reason the authority also departs. Unless you’re giving a church more authority than God.
Is the Bible the infallible word of God or not? Is God the source of truth or not? Is God the final authority or is He not? Then it stands to reason that His word is the final authority, not any church. So I don’t believe that verse is saying what Catholics say it is because that would then kind of make a god out of the church, giving it superior authority above what God has said in His word. The Bereans didn’t check with a church to find out if what Paul told them was true, they checked the Scriptures.