Even if we count Míriel as 'dead' - after all, her fëa has gone to the halls of Mandos - she still could not be labelled as 'slain'.
Apparently, it seemed possible to the Ainur and Eldar that a spirit may leave a body and not return like this; but that one of them might be slain because of the action of another was yet hard to imagine. Fëanor would have considered it murder if the Silmarils had been taken forcefully from him, resulting in his own agony.
What is more, the passing of Míriel was known to everybody, so Mandos' remark could have hardly surprised anyone as it did had they considered it as a comment on Míriel.
|