Necronomicon- ’Umr at-Tawil

For the rite of the Silver Key, as practiced by Randolph Carter in that black, haunted cave within a cave, did not prove unavailing. From the first gesture and syllable an aura of strange, awesome mutation was apparent—a sense of incalculable disturbance and confusion in time and space, yet one which held no hint of what we recognise as motion and duration. Imperceptibly, such things as age and location ceased to have any significance whatever. The day before, Randolph Carter had miraculously leaped a gulf of years. Now there was no distinction between boy and man. There was only the entity Randolph Carter, with a certain store of images which had lost all connexion with terrestrial scenes and circumstances of acquisition. A moment before, there had been an inner cave with vague suggestions of a monstrous arch and gigantic sculptured hand on the farther wall. Now there was neither cave nor absence of cave; neither wall nor absence of wall. There was only a flux of impressions not so much visual as cerebral, amidst which the entity that was Randolph Carter experienced perceptions or registrations of all that his mind revolved on, yet without any clear consciousness of the way in which he received them.
     By the time the rite was over Carter knew that he was in no region whose place could be told by earth’s geographers, and in no age whose date history could fix. For the nature of what was happening was not wholly unfamiliar to him. There were hints of it in the cryptical Pnakotic fragments, and a whole chapter in the forbidden Necronomicon of the mad Arab Abdul Alhazred had taken on significance when he had deciphered the designs graven on the Silver Key. A gate had been unlocked—not indeed the Ultimate Gate, but one leading from earth and time to that extension of earth which is outside time, and from which in turn the Ultimate Gate leads fearsomely and perilously to the Last Void which is outside all earths, all universes, and all matter.
     There would be a Guide—and a very terrible one; a Guide who had been an entity of earth millions of years before, when man was undreamed of, and when forgotten shapes moved on a steaming planet building strange cities among whose last, crumbling ruins the earliest mammals were to play. Carter remembered what the monstrous Necronomicon had vaguely and disconcertingly adumbrated concerning that Guide.
     “And while there are those,” the mad Arab had written, “who have dared to seek glimpses beyond the Veil, and to accept HIM as a Guide, they would have been more prudent had they avoided commerce with HIM; for it is written in the Book of Thoth how terrific is the price of a single glimpse. Nor may those who pass ever return, for in the Vastnesses transcending our world are Shapes of darkness that seize and bind. The Affair that shambleth about in the night, the Evil that defieth the Elder Sign, the Herd that stand watch at the secret portal each tomb is known to have, and that thrive on that which groweth out of the tenants within—all these Blacknesses are lesser than HE Who guardeth the Gateway; HE Who will guide the rash one beyond all the worlds into the Abyss of unnamable Devourers. For HE is ’UMR AT-TAWIL, the Most Ancient One, which the scribe rendereth as THE PROLONGED OF LIFE.”
...

A moment later Carter knew that this was so, for the Shape had spoken to his mind without sound or language. And though the name it uttered was a dreaded and terrible one, Randolph Carter did not flinch in fear. Instead, he spoke back, equally without sound or language, and made those obeisances which the hideous Necronomicon had taught him to make. For this Shape was nothing less than that which all the world has feared since Lomar rose out of the sea and the Winged Ones came to earth to teach the Elder Lore to man. It was indeed the frightful Guide and Guardian of the Gate—’Umr at-Tawil, the ancient one, which the scribe rendereth the Prolonged of Life.
The Guide knew, as he knew all things, of Carter’s quest and coming, and that this seeker of dreams and secrets stood before him unafraid. There was no horror or malignity in what he radiated, and Carter wondered for a moment whether the mad Arab’s terrific blasphemous hints, and extracts from the Book of Thoth, might not have come from envy and a baffled wish to do what was now about to be done. Or perhaps the Guide reserved his horror and malignity for those who feared. As the radiations continued, Carter mentally interpreted them in the form of words.
     “I am indeed that Most Ancient One,” said the Guide, “of whom you know. We have awaited you—the Ancient Ones and I. You are welcome, even though long delayed. You have the Key, and have unlocked the First Gate. Now the Ultimate Gate is ready for your trial. If you fear, you need not advance. You may still go back unharmed the way you came. But if you choose to advance . . .”
     The pause was ominous, but the radiations continued to be friendly. Carter hesitated not a moment, for a burning curiosity drove him on.
     “I will advance,” he radiated back, “and I accept you as my Guide.”

- Through the Gates of the Silver Key, part III