It's a word that doesn't have an exact English equivalent... Webster's offers "Belief; faith; fidelity; truth; verity; veracity" as approximate synonyms.
In a sense, it seems to be the opposite of hypocrisy. It conjures up thoughts of integrity, community, and stick-with-it-ness, and I wonder if our society of constant competition for our moment-to-moment attention, the anonymity of the crowd, and the pursuit of the immediate gratification of a consumer, is leading us away from this notable, ancient concept.
Already, the word is almost lost, remaining only as the root word of "betrothal", but perhaps even that term, and its meaning, will soon be lost.
As always, I disclaim innocence, but I'll remember this term the next time I'm tempted to sit in front of the TV and flip channels, and the next time I meet someone...