There are five levels of life: The First Level of Life is that of our life, which is very restricted. 

The Second Level of Life is that of Khidr and Ilyas (May Allah grant them peace), which is free to an extent. That is to say, they can be present in numerous places at the same time. They are not permanently restricted by the requirements of humanity like we are. They can eat and drink like us when they want to, but are not compelled to like we are. Saints who attain to direct vision and knowledge of reality have reported virtually unanimously their adventures with Khidr and these elucidate and prove this level of life. One of the degrees of sainthood, even, is called the degree of Khidr. A saint who reaches it receives instruction from Khidr and meets with him. But it sometimes happens that such a person is mistakenly thought to be Khidr himself. 

The Third Level of Life is that of Idris and Jesus (May Allah grant them peace), which is removed from the requirements of humanity, and is an angelic level of life and acquires a luminous fineness. Quite simply, Idris and Jesus are present in the heavens with their earthly bodies, which have the subtlety of bodies from the World of Similitudes and the luminosity of astral bodies. There is a Hadith that states that at the end of time, Jesus (Upon whom be peace) will come and will act in accordance with the Shari‘a of Muhammad (UWBP). This indicates that at the end times the religion of Christianity will be purified and divest itself of superstition in the face of the current of unbelief and atheism born of naturalist philosophy, and will be transformed into Islam. At that point, on the one hand the collective personality of Christianity will kill the fearsome collective personality of irreligion with the sword of heavenly revelation; and on the other, representing the collective personality of Christianity, Jesus (Upon whom be peace) will kill the Dajjal, who represents the collective personality of irreligion; that is, he will kill atheistic thought. 

The Fourth Level of Life is that of the martyrs. According to the Qur’an, the martyrs are at a level of life higher than that of the other dead in their graves. Since they sacrificed their worldly lives in the way of truth, in His perfect munificence Almighty Allah bestows on them in the Intermediate Realm a life resembling earthly life, but without its sorrows and hardships. They do not know themselves to be dead and suppose only that they have gone to a better world. Enjoying themselves in perfect happiness, they do not suffer the pains of separation that accompany death.2 For sure the spirits of the dead are immortal, but they know they are dead. The happiness and pleasure they experience in the Intermediate World are not equal to the martyrs’ happiness. Like if two men in their dreams enter a beautiful palace resembling Paradise: one knows that he is dreaming and the pleasure and enjoyment he receives are deficient. He thinks: “If I wake up, all this enjoyment will disappear.” While the other man is unaware that he is dreaming, and he experiences true pleasure and delight. Thus, the martyrs partake of life in the Intermediate Realm differently to the other dead. It has been definitely established by innumerable incidents and narrations that they manifest life in the way described above and suppose themselves to be alive. Indeed, their level of life has been illuminated and proved on numerous occasions by such occurrences as Hamza (May Allah be pleased with him) – the lord of the martyrs – protecting those who have recourse to him, and his performing and making performed tasks in this world. I myself, even, had a nephew and student called Ubeyd. He was killed at my side and in my place and became a martyr. Then, when I was being held as a prisoner-of-war at a place three months’ distance away, I entered his grave in a true dream, which was a sort of dwelling-place under the earth, although I did not know where he was buried. I saw him living the martyrs’ level of life. He evidently thought that I was dead and said that he had grieved over me greatly. He thought he was alive, but having retreated before the Russian invasion, had made himself a good home under the ground. Thus, owing to such indications, my unimportant dream convinced me about the above-mentioned truth as certainly as having witnessed it. 

The Fifth Level of Life is that of the spirits of the dead in their graves. Yes, death is a change of residence, the liberation of the spirit, a discharge from duties; it is not annihilation, non-existence, and a going to nothingness. Many evidences illuminate and prove this level of life, such as the innumerable occasions the spirits of saints have assumed forms and appeared to those who unveil the realities, and the other dead have communicated with us while awake or sleeping and have told us of things that are conformable with reality. In fact, the Twenty-Ninth Word, which is about the immortality of man’s spirit, demonstrates this level of life with incontrovertible proofs.

Source: 1st Letter, Risale-i Nur Collection.