§ Of Beren and Lúthien The Silmarillion

Thus the quest of the Silmaril was like to have ended in ruin and despair; but in that hour above the wall of the valley three mighty birds appeared, flying northward with wings swifter than the wind. Among all birds and beasts the wandering and need of Beren had been noised, and Huan himself had bidden all things watch, that they might bring him aid. High above the realm of Morgoth Thorondor and his vassals soared, and seeing now the madness of the Wolf and Beren's fall they came swiftly down, even as the powers of Angband were released from the toils of sleep.