One can speak of pursuing only that which is most important. But it is never that simple. Every decision that we make in life will, inevitably, lead toward that which is most important, or away from it. But like a road through the mountains, that path is seldom straight. When we say “x” is most important, this does not mean that “y” and “z” are NOT important, but that other things are simply less important. Also, this does not mean that “y” and “z” can simply be ignored, at any expense.
Within Eastern Orthodoxy, they say that there is only one path to eternal life, not two, as some suggest, when considering either the married path or the monastic path. These are one path with different emphases. When one chooses the married path, one is automatically taking on the responsibilities of things “not-spiritual” (which really is a misnomer, for God uses all things for our spiritual growth, we just need to learn to see that).
So ultimately, yes, the one most important thing is our sanctification, but the path of sanctification is typically not what we may think it is. To use a metaphor, one does not become a good runner by studying it, but by practicing it, often, and it often is very uncomfortable or even painful. To the same end, our sanctification will be uncomfortable, confusing and even painful, but when we learn to trust God for leading us down that path, at least we won’t fall into despondency.
I, of all people, need to hear this truth more than anyone.