The Oath of Felagund

“The sons of Finarfin bore most heavily the brunt of the assault, and Angrod and Aegnor were slain; beside them fell Bregolas lord of the house of Bëor, and a great part of the warriors of that people. But Barahir the brother of Bregolas was in the fighting further westward, near to the Pass of Sirion. There King Finrod Felagund, hastening from the south, was cut off from his people and surrounded with small company in the Fen of Serech; and he would have been slain or taken, but Barahir came up with the bravest of his men and rescued him, and made a wall of spears about him; and they cut their way out of the battle with great loss. Thus Felagund escaped, and returned to his deep fortress of Nargothrond; but he swore an oath of abiding friendship and aid in every need to Barahir and all his kin, and in token of his vow he gave to Barahir his ring. ” -- J. R. R. Tolkien: The Silmarillion, chapter 18: Of the Ruin of Beleriand and the Fall of Fingolfin