What is the biblical support that the Catholic Church is the custodian of truth?

The doctrine of papal infallibility is not founded on biblical texts specifically. It is founded on the "biblically supported" doctrine that the church is the *custodian of truth*. What is the scriptural support for the Catholic church's claim that they are the custodians of truth? What does it mean to be the *custodian of truth.* Does this mean that they believe in modern revelation and receive direction from God?