Sanctified weapons, shields, and armor are considered permanently blessed and able to harm the undead in the hands of a cleric or paladin. White ora and eonake are naturally sanctified. Clerics and paladins can use the ASSESS command to check an item for this property. Sanctified items will also be identified as holy items via loresinging. Sanctified items are not otherwise blessable when used by other professions.
The Holy Weapon (1625) spell can be used on any weapon by a paladin to bond to the weapon and make it sanctified.
The blessed property of shields and armor is only useful for offensive shield maneuvers and Bull Rush, which are available to paladins but not clerics. Paladins can also Consecrate (1604) any sanctified item to imbue it with temporary plasma flares (against any enemy, not just undead).
Plain white ora sanctified weapons can typically be purchased in clerical shops. Sanctified items can be found in the treasure system made of materials other than white ora and eonake. It is possible for a sanctified weapon to also have weighting and flares, and for sanctified armor to have padding and flares.