Little is known with certainty concerning the Classic Maya priesthood. Iconographically, there can be no serious doubt but that the aged, ascetic figures depicted as writing and reading books, aspersing and inaugurating dignitaries and kings, and overseeing human sacrifice, represent professional priests and high priests at court. Certain hieroglyphic titles of noblemen have been interpreted as priestly ones (e.g., "ajk'uhuun", possibly 'worshipper', "yajaw k'ahk" 'master of fire'). The king ("k'uhul ajaw" or 'holy lord'), too, acted "ex officio" as a priest.