Man shall not live on bread alone but by every word of God.
The church is the body of believers, not a building, or a foundation of truth.
St. Paul was very plain about it....the Word of God encompasses both written and oral knowledge, both passed on by the Apostles. The idea that "only the written Bible" is the authority just doesn't fit the historical reality, and was a complete modern innovation invented out thin air.
"The church is the body of believers, not a building, or a foundation of truth."
If the church isn't the foundation of truth, nothing is. Yes, the PHYSICAL church on earth is the body of baptized believers. But like it or not, that ties the Protestants back into the Catholic church.