The Apostle Test

Rev 2:2 I know thy works, and thy labour, and thy patience, and how thou canst not bear them which are evil: and thou hast tried them which say they are apostles, and are not, and hast found them liars:

For some reason it never occured to me what this verse is saying...try the apostles to see which are liars? How could that be? And how do we try the apostles?

By learning what the Bible says.