The Magnius Lock

You touch a closed door, window, gate, chest, or other entryway, and it becomes locked for the duration. You and the creatures you designate when you cast this spell can open the object normally. You can also set a password that, when spoken within 5 feet of the object, suppresses this spell for 12 seconds. Otherwise, it is impassable until it is broken or the spell is dispelled or suppressed. Casting knock on the object suppresses arcane lock for 1 minute.

The object is considered permanently sealed to the untrained eye and a magical iron key is visible on the surface.

Any attempt made to either break or open the lock immediately alerts the caster of tampering.