Gandalf's body was mortal, subject to the physical rules of Middle Earth, but his spirit was immortal, as seen when he died as Gandalf the Grey and resurrected as Gandalf the White.
El cuerpo de Gandalf era mortal, sujeto a las leyes físicas  de la Tierra Media, pero su espíritu era inmortal, como se ve cuando muere  como Gandalf el Gris y resucita como Gandalf el Blanco.