Beautiful, isn't it? Quite rare because light has to be at just the right angle to form this fire rainbow. Some day I hope to see such a beautiful thing in the heavens with my own eyes. That is something to look forward to, indeed. The Psalmist was looking forward to seeing God and one can only imagine what that would be like. Its interesting to me that he asks for just one thing. Read the verse and I think you will begin to see a depth in it that is not obvious at first glance.
Psa 27:4 One thing have I asked of the LORD, that will I seek after: that I may dwell in the house of the LORD all the days of my life, to gaze upon the beauty of the LORD and to inquire in his temple.
I can only imagine what it will be like to be in God's presence, to consider his form and speak with him. What would he say, how would I comphrend it and how would I respond? Good questions, all. I honestly don't know the answers, but I think it would be better than any fire rainbow that I may ever see. One thing is for sure, the best way to start begins by looking up; at least you are headed in the right direction. Oh yes, you have to look and keep on looking; that's what the "one" in the verse is all about.