I have to admit that I am not at all an expert on Søren Kierkegaard, the great Danish philosopher and theologian; although I think I can claim to be somewhat of an expert on The Silmarillion of JRR Tolkien. My ideas on Søren Kierkegaard mostly have to do with his idea of the three spheres, the aesthetic, the ethical and the religious. According to Kierkegaard, people progress from a simple fondness for pleasure and amusement, to a more sober, committed ethical life. But past that, they go through another transformation, to the religious, which can be paradoxical, since embracing religious values can involve seemingly abandoning ethical values. Kierkegaard's example of this is in Abraham sacrificing Isaac, allowing the voice of God to overpower normal ethical laws forbidding murder.
The central theme of The Silmarillion is the greed or even lust that many of the characters have for the Silmarils, three gems of incredible beauty that reflect and refract an unearthly light. Many of the characters, including the Elves who had studied under the archangels themselves. fall from their nobility in their quest to capture just a glimpse of the light of the jewels. Are these characters showing the fragility of their ethical selves, and falling into a simple aesthetic greed? Since the characters that are corrupted by love of the Silmarils are still in other ways full of virtue, it would seem not. Also, the Silmarils are not just fancy gems, but hold the lost light of the Two Trees, which is a refraction of the light that God himself put into his creation. In addition, some of the characters have taken an oath to call down everlasting darkness upon themselves if they do not pursue the Silmarils. In other words, it seems that the characters that pursue the Silmarils are trying to do so because they are fleeing from the absence of God into the presence of God. They are inspired by religious awe.
Does Tolkien then feel, with Kierkegaard, that someone committed enough to a religious goal such as beholding God is allowed to break normal ethical laws, to the point of fratricide? Although The Silmarillion is a complicated work, I feel that Tolkien does not hold to such a position. For one thing, Tolkien was a Catholic, and therefore would have probably put a much higher value on social ethics than Kierkegaard, one of the most radical of Radical Protestants. Internally, there is much evidence that pursuit of the light is not all there is, because as I have written before, the Elves who were most exposed to the light do not seem to be any closer to following God's purposes than those who were not be exposed to it. In the later chapters of the Silmarillion, God is not mentioned as much as he was in the early creation mythos section of the book, but presumably the fact that God existed and held a standard of justice out was not lost on many of the Elves who were involved in the wars. Although it is never directly stated, I believe that they would have in some ways had their own idea of religious awe and following God that did not confine itself to the brilliant light of the Silmarils. Also, many other things are given as examples of God's work in the mythos, other than light: language, water, sound, and trees are all spoken of as things that are somehow blessed or sanctified, and the Elves and Men that show special attention to these are following the call in their own way.
So I would say that Tolkien does believe that there is a special type of religious awe that in some ways is set apart from normal ethical consideration. He does show a strong sympathy for characters such as Fëanor, even though they commit grevious sins. However, Tolkien would not at all believe that this type of drive towards the light supersedes normal ethical consideration. In fact, he seems to be suggesting throughout this work (and The Lord of the Rings as well), that such a drive may ironically and subtly take people further away from what they think they are pursuing.