whatsoever you shall bind on earth shall be bound in heaven....whatsoever you shall loose on earth shall be loosed in heaven.......................infallible
http://www.merriam-webster.com/dictionary/infallible
infallible : incapable of error : unerring *an infallible memory*
2: not liable to mislead, deceive, or disappoint : certain *an infallible remedy*
3
:incapable of error in defining doctrines touching faith or morals
Binding and loosing is not infallibility. It would be exercising authority, but it is not being without error.