"Any knowledge is that of the absolute reality"Frithjof Schuon includes in his work a wide field of spiritual research, something characteristic to Perennialists and Traditionalists. The Islamic branch of human spirituality is strongly present through the prism of sufism. Christianity is also analyzed in the desire by Schuon to demonstrate the transcendent unity of religions. Because I am personally interested in Islamic philosophy and exegesis I've concentrated my attention more on these aspects, needless to say that this limits the richness of the text. A beginner will find a great (albeit steep) introduction into the inner aspects of Islam, that's why I also recommend the following: "Islam. Introduction in the esoteric doctrine" by Titus Burckhardt, ”Understanding Islam” by Frithjof Schuon, ”History of Islamic Philosophy” by Henry Corbin and many more.
"(...) to know (understand) is to know Divinity"
"(...) the simple fact that man makes use of all his faculties in prayer, it doesn's mean that emotions need to be taken as an end by themselves and let the to alter the doctrinal truths"
"Man is the only terrestrial being that can purify itself while being conscious of its flaws"
"Contrary to that is generally stated, meditation does not posses any virtue of bringing by itself enlightenment, (...) it needs to distance the interior obstacles that opposed to understanding, not "new" understanding, but "preexisting" and "innate".
In conclusion, the Eye of the Heart by Frithjof Schuon is a book of the heart because you will not want to read it once, but you will want to come back to it from time to time, to taste the pure wisdom it has to offer. I am far from making a compete review of the book, I have left out many aspects because what matters is reading the book for yourselves.