"And do not say about those who are killed in the way of Allah, 'They are dead.' Rather, they are alive, but you perceive [it] not," regarding the nature of the life that is the life of the martyrs.
Muhammad said: "Amwat" (dead) is in the nominative case (marfu') implying: they are dead; and likewise "bal ahya'" (rather, they are alive) implies: rather, they are alive.
Yahya [narrated] from al-Mu'alla, from 'Abd al-Rahman ibn Tharwan, from Hudhayl, from 'Abdullah ibn Mas'ud, who said: "The souls of the martyrs are in the crops of green birds that graze in Paradise wherever they wish, then they seek shelter in lanterns suspended from the Throne."