The wise old man appears in dreams in the guise of a magician, doctor, priest, teacher, professor, grandfather, or any other person possessing authority. The archetype of spirit in the shape of a man, hobgoblin, or animal always appears in a situation where insight, understanding, good advice, determination, planning, etc., are needed but cannot be mustered on one's own resources.
Jung's foundational definition of the Old Wise Man as the compensatory archetype of spirit that constellates specifically when conscious resources of insight and direction prove insufficient.
, The Archetypes and the Collective Unconscious, 1959thesis