§ Of the Voyage of Eärendil and the War of Wrath The Silmarillion

Bright Eärendil was then lord of the people that dwelt nigh to Sirion's mouths; and he took to wife Elwing the fair, and she bore to him Elrond and Elros, who are called the Half-elven. Yet Eärendil could not rest, and his voyages about the shores of the Hither Lands eased not his unquiet. Two purposes grew in his heart, blended as one in longing for the wide Sea: he sought to sail thereon, seeking after Tuor and Idril who returned not; and he thought to find perhaps the last shore, and bring ere he died the message of Elves and Men to the Valar in the West, that should move their hearts to pity for the sorrows of Middle-earth.