In general, birth order in the Bible reflects the progression of spiritual states, but the specifics of those states depends greatly on context: who the people in question are, and whether we’re talking about spiritual states as they flow to us from the Lord, or spiritual states as we advance through them to approach the Lord. For example, Esau was older than Jacob (by minutes, but it mattered), and as the elder represents a more internal spiritual state: the desire for good, and the ideas that flow from that desire. Jacob represents a more external state: the understanding of ideas that lead to good. The switched blessing, with Jacob getting the blessing Isaac meant for Esau, shows that to progress in life we need to put our understanding first for a while, though ultimately our loves will catch up and ultimately determine our true character. A similar thing happens when Jacob crosses his hands to give Ephraim, the younger of Joseph’s sons, the primary blessing over his older brother Manasseh. Both those cases describe blessings coming from the Lord, with the highest states coming from Him and extending down through lower states to get to us. There is a sort of opposite dynamic in the story of Leah and Rachel. There Jacob (representing the Lord himself, as a human, in His childhood) is advancing from more external states to more internal ones. In this case, then, the older daughter, Leah, represents a more external state which He had to work through to reach the more internal state represented by Rachael.

A "house" is essentially a container -- for a person, a family, several families or even a large group with shared interests (think of the term "houses of worship.") In the Bible, a "house" is also a container, but for spiritual things rather than natural things. In various uses a "house" can represent part of the mind, the whole mind, a whole person or even a church. The other nuance to the word "house" is that it is generally used in regards to our affections and desires rather than our thoughts and principles. This makes sense; we tend to engage our thoughts and rationality when we are out in the world doing our work, but when we are inside our houses we are driven most by love for our families and the desire to be good to those we love. So "house" tends to represent the things we want and care about -- which are ultimately the things that define us.