[HerenIstarion]

More than two months passed since the quote was given, and no answer found. so I count myself victorious, and reveal the answer. I'll give the whole passage, so to make it clearer:

But Túrin said:'Beyond the marches of Doriath my heart urges me; I long rather for assault upon the Enemy, than for defence of the borderlands'

'Then you must go alone, said Thingol. 'The part of my people in the war with Angband I rule according to my wisdom, Túrin son of Húrin. No force of the arms of Doriath will I send out at this time; nor in any time that I can yet foresee'

'Yet you are free to go as you will, son of Morwen' said Melian. 'The Girdle of Melian does not hinder the going of those that passed in with our leave'

Unless wise counsel will restrain you, said Thingol.
What is your counsel, lord? said Túrin.
'A Man you seem in stature,' Thingol answered, 'but nonetheless you have not come to the fullness of your manhood that shall be. When that time comes, then, maybe, you can remember your kin; but there is little hope that one Man alone can do more against the Dark Lord than to aid the Elf-lords in their defence, as long as that may last'

Then Túrin said: 'Beren my kinsman did more'
'Beren, and Lúthien' said Melian. 'But you are over-bold to speak so to the father of Lúthien. Not so high is your destiny, I think, Túrin son of Morwen, though your fate is twined with that of the Elven-folk, for good or for ill. Beware of yourself, lest it be ill.'

Then after a silence she spoke to him again, saying: 'Go now, fosterson; and heed the counsel of the king. Yet I do not think that you will long abide with us in Doriath after the coming of manhood. If in days to come you remember the words of Melian, it will be for your good: fear both the heat and the cold of your heart.

First person to read this may proceed