Originally Posted by BGwiki
Barspells increase Magic Evasion against specific elements or statues.
Bar-status Spells : These increase Magic Evasion against a specific status effect.
Status effects also often have an element, so pairing a Barspell of the appropriate element with the Barspell for the status effect you are trying to avoid will increase your Magic Evasion against that status even further. If you increase it enough, you should consistently Resist it.
Very little is known about Status Barspells, because their potency is not easily viewable like Elemental Barspells. Their potency likely depends on Enhancing magic, though the specific equation is unknown, and they use a different equation for duration: