There's a fair amount of Libra in my birth chart - Mercury and Venus are both there as is Neptune. Maybe that's why I usually try to look at both sides of a question. With that in mind this post is going to be about the importance of esoteric understanding if one wants to make real spiritual progress. It is neither sufficient nor necessary for salvation but it is very helpful and, though the intellectual mind is not the key to unlocking the door of spiritual truth, it can certainly guide the key to the lock.
Faith and knowledge are often separated and regarded as almost in opposition but I see them as twins with each one both complementing and deepening the other. Without faith knowledge is dry and spiritually sterile. Without knowledge faith can be impotent and immature and rooted in ignorance. Ignorance is never good. It will likely lead to error and then becomes faith in what is false. What use is that?
Esoteric teachings are simply a guide to the higher aspects of the human being, where we have come from, where we should be going and how we get there from here. Then they describe the spiritual structure of the universe. They are, properly considered, the knowledge aspect of religion and so are a form of spiritual science. Like material science they can be abused but in themselves they are good because they are founded on truth though I would add the strict proviso that any teaching calling itself esoteric needs to be subjected to the rigour of intuition, common sense and cast in the light of the reality of Christ. If it conflicts with the latter, it can be rejected.
There may have been a time when knowledge of the higher worlds was relatively unimportant for the work we need to do in this world to grow and develop spiritually but now human beings have evolved their minds and the mind needs to be catered for. It must have food. If it does not have real knowledge it will have false knowledge and it will act according to that in ways that would not have been possible before as it has more agency. Therefore, you could say that esoteric understanding has become more important. A developing mind has to have something to know.
Moreover, there is a God-given impulse in the mind pushing it towards growth. We need to understand. We are in fact obliged to understand and esoteric teachings provide some form of understanding. They are not perfect because we are still very limited beings but we are growing towards the light and esoteric teachings can be a kind of fertiliser that help us to grow. As long, that is, as they are balanced by growth in the spiritual and moral sense. I refer back to the previous post.