Querent

A querent (derived, according to the "Oxford English Dictionary", from the Latin "quærēns" "seeking", the present participle of "quærere" "to seek, gain, ask") is "one who seeks".
"Querent" became used to denote "a person who questions an oracle" because it is usually when one has a problem that requires otherworldly advice that one would seek out the oracle in the first place. This oracle may simply be a divinatory technique, such as the "I Ching", that is manipulated by the querents themselves without recourse to any other human agency. Alternatively it may involve another person, someone perhaps seen as a "fortune teller" – particularly a practitioner of tarot reading or other form of mediumship – from whom advice is sought.