Trustworthy and True
Certain things are completely trustworthy. These things are called "infallible." Certain teachings of the Church are infallible; for example, the gospel message of salvation and the doctrines regarding the Trinity and the deity of Christ.
For those of you who aren't convinced that the doctrine of infallibility is important, consider it this way. Why should we believe something that is not true? Or, should we believe in error? Of course we should always prefer truth to error. Thus, we should believe things that are infallibly true; there is no chance of error.
It is difficult as a Christian to know who and what to believe. Certainly we can believe the Bible. Here is the procedure I follow...