Banisher Priest — ruling 1

If Banisher Priest leaves the battlefield before its triggered ability resolves, the target permanent won't be exiled.

Banisher Priest — ruling 2

Auras attached to the exiled permanent will be put into their owners' graveyards. Any Equipment will become unattached and remain on the battlefield. Any counters on the exiled permanent will cease to exist. When the card returns to the battlefield, it will be a new object with no connection to the card that was exiled.

Banisher Priest — ruling 3

If a token is exiled this way, it will cease to exist and won't return to the battlefield.

Banisher Priest — ruling 4

If an Aura is exiled this way, its owner chooses what it will enchant as it returns to the battlefield. An Aura put onto the battlefield this way doesn't target anything (so it could be attached to a permanent with shroud, for example), but the Aura's enchant ability restricts what it can be attached to. If the Aura can't legally be attached to anything, it remains in exile for the rest of the game.

Banisher Priest : règles, fonctionnement et interactions (MTG)

Banisher Priest is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

When this creature enters, exile target creature an opponent controls until this creature leaves the battlefield.

How it works : Banisher Priest

Original English text — Wizards of the Coast / Scryfall

#1July 1, 2013· Wizards of the Coast
If Banisher Priest leaves the battlefield before its triggered ability resolves, the target permanent won't be exiled.
No other card is named in this ruling.
#2July 1, 2013· Wizards of the Coast
Auras attached to the exiled permanent will be put into their owners' graveyards. Any Equipment will become unattached and remain on the battlefield. Any counters on the exiled permanent will cease to exist. When the card returns to the battlefield, it will be a new object with no connection to the card that was exiled.
No other card is named in this ruling.
#3July 1, 2013· Wizards of the Coast
If a token is exiled this way, it will cease to exist and won't return to the battlefield.
No other card is named in this ruling.
#4July 1, 2013· Wizards of the Coast
If an Aura is exiled this way, its owner chooses what it will enchant as it returns to the battlefield. An Aura put onto the battlefield this way doesn't target anything (so it could be attached to a permanent with shroud, for example), but the Aura's enchant ability restricts what it can be attached to. If the Aura can't legally be attached to anything, it remains in exile for the rest of the game.
No other card is named in this ruling.