Originally supposed to be named "War", and it would have been an Incarnation, yet the ability would not fit. (I couldn't find art which was fitting for either an Incarnation or a Spirit Avatar either, and if it was the latter, it would need to be 3-coloured to differentiate it from the original cycle). Human Knight fits the art, but doesn't quite capture what I had in mind.
Red and white are both colours which allow for individuals to devote themselves to a greater cause (black too, at times, but at its core, this concept isn't as evident); red from passion, and white from ethical/moral obligation. Together, the two philosophies as one most strongly conveys religious/ideological zeal (combining the aspects of morality and impulse), with the aspects of chaos and order mostly cancelling themselves out, unless the colours are not equally represented.
Mechanically, with proper regard towards flavour, R/W can encompass much more than combat abilities, as they have thus far been iconically represented.
Unlike Panglacial Wurm, the card text doesn't need to specify "search". Scrying, searching, being revealed from the top of the library, or any other condition which allows you to look at the card in your library would allow also for you to cast it from your library.
Double red and lack of protection from red is for balancing reasons.