The Golden Dawn gave the fifth trump the letter Vau, the sign Taurus, and the sixteenth path of the Tree of Life, from Chokmah to Chesed. Vau means a nail or a hook, the letter that joins, and the fit with a mediating priesthood is neat enough that it is easy to forget the assignment is a Victorian one. It descends from Eliphas Levi's system of the 1850s by way of the order's own revisions, and no earlier source connects this card with Taurus.
The card is read in two directions and the split is real. Read positively it is teaching, orthodoxy that works, initiation into an established body of knowledge, mentorship, marriage in its formal sense, and the value of doing a thing the way it has been done. Read critically it is conformity, institutional pressure, an answer accepted because of who gave it, and the substitution of doctrine for judgement. Neither reading is the reversal of the other; both are available upright, and which one a reader takes usually says as much about the reader as about the spread.
Crowley's treatment complicates it further, since for him the card marks the passage between aeons and therefore a hierophant whose authority is expiring. That is a specifically Thelemic reading and should not be exported unlabelled into general practice.
The useful question this card puts is not whether tradition is good or bad, but whether the querent is currently inside an institution that is answering their question for them before they have finished asking it. Reversed, Waite gives unconventionality and the breaking of a bond; readers who do not turn cards generally get the same reading from an upright Hierophant sitting next to a card of disruption, and lose nothing by it.