Freire believes that both teacher and pupil have wisdom, albeit different kinds of wisdom. He does not view the teacher as "knowing" and the pupil as "unknowing". He believes that the authoritarian role of the teacher is critical to the pupil's development, in other words that structure is important, but that this authority should not be abused. He favors a democratic environment for learning, as opposed to an authoritarian or permissive one. His is a more informal approach to educating with an emphasis on dialogue. He opposes "banking", in which the educator makes "deposits" in the pupil. He places great importance on developing consciousness and work with the "oppressed", people who did not usually have a voice in the world.
Why would the Freire ideas, philosophies or approaches be a useful "lens" in the study of Humanities?
Because Humanities is a study of things that deal with humanism, dialogue seems like an obvious approach to teaching and learning. Part of what Humanities deals with is the human experience, so discussion is important. A learning environment that has structure, but is relaxed and respectful of all perspectives can make learning possible for a wider range of people. And while making "deposits" in a pupil might be appropriate in a math, science or history class, it wouldn't be in a Humanities or Philosophy class. Here, Freire's approach makes more sense.
I thought the Reader-Response Criticism approach or perspective had commonalties with Freire's philosophies. Here, it is not only the text that is important to the learning process, but also the effect of the text on the reader. The text is interpreted through the personal identity and experience of the reader.
I also saw a similarity with the New Historicism approach, because that is a less authoritarian way of viewing art and literature. The Multicultural Criticism approach emphasizes giving voice to those who traditionally don't have one, and I read some of Freire's philosophies in this, as well.