Pride Goeth Before a Fall

Meaning:
The actual Bible verse (King James version) is "Pride goeth before destruction, and an haughty spirit before a fall." It means that the next step after being all puffed up with arrogance could be falling flat on your face. Well, according to what I know, 'Pride comes before a fall' means that one becomes over confident and stops thinking sensibly when success goes to one's head and which is a sure indication of the fact that that person is bound to suffer or face disappointment because of the wrong decisions that he or she might make. In other words too much arrogance and self pride are sure to bring bad and disappointing results.

Origin:
The proverb comes from the Old Testament - Proverbs 16:18 "Pride goeth before destruction, and an haughty spirit before a fall."
Herman Melville rendered essentially the modern version in 'The Piazza Tales' (1856).

Sources:
http://wiki.answers.com/Q/What_does_%27Pride_comes_before_the_fall%27_mean
http://kingjbible.com/proverbs/16.htm
http://www.phrases.org.uk/bulletin_board/32/messages/1321.html