Is it permissible to describe things as "immortal" or "everlasting" (khalid) – such as "this is an immortal book," "his morals are everlasting," "his story is everlasting," "his stances are everlasting," "his biography is everlasting" – without intending to describe persons with this attribute?

There is no legal impediment to describing something as eternal, as the origin of eternity is permanence and steadfastness. Ibn Faris, in "Maqayis al-Lughah," explained that the letters kha, lam, and dal signify steadfastness and adherence, and he mentioned examples such as "Jannat al-Khuld" (the Garden of Eternity) and "akhlad ila al-ard" (inclined to the earth). The Prophet (peace be upon him) approved the name "Khalid" and did not change it. The description does not imply imperishability but rather a long duration and permanence until a certain time.