Let me say up-front that Meher Baba is my spiritual Master, who I have followed since mid-1974, when I was in my late teens. I believe him to be the Avatar of this age (Avatar being another word for Messiah, Buddha, Prophet). So I speak from over 30 years' personal experience of applying this book in my daily life, plus meeting with various of Baba's direct disciples (one of whom, Don E. Stevens, is featured in my documentary, "In Another Life").
The teaching of a Realized being is fundamentally different from that of an ordinary person, no matter how intelligent. This teaching comes from inside you, and this is because the Realized master is consciously identified with the true Self residing in everyone. Therefore, it is your own fully-conscious Self writing to you what you already know deep-down inside. It doesn't read like philosophy, turning your mind into a pretzel. It reads like bubbles of wisdom rising to the surface of your mind from the depths. But, this takes receptivity. It is my personal theory that each key idea in Discourses takes many lifetimes of experience to be able to accept. All of the life-lessons that it takes so much suffering to learn, are already contained in this work--but being receptive generally requires going through the experience. If you can listen and learn without having to go through the suffering, lucky you!
The Discourses were just what the name implies, discourses given by Meher Baba to his direct disciples over the course of several years, and then compiled and edited by the followers later on under Baba's supervision. I can't encapsulate everything they do in a short review, but one of the things they do is show how to bring spirituality into all aspects of everyday life. Meher Baba demonstrates how the Divine is connected to ordinary life and how everything in life can be spiritualized in the journey Homeward. Discourses shows us just how practical spirituality can, and must, be. I think of it as the instructional manual life was supposed to come with. I know Christians claim this of the Bible, and they are right to the extent that one can decipher the distortions arising from thousands of years of editing.* But this is coming from the same inner state of Realization, directly from the horse's mouth as it were. It is not veiled in poetry, mythology or symbolism; its power has not been diluted by time, editing or translation; it is not a second or third-hand imitation; it is not guesswork; it is not a system of thought or a constructed cosmology. It is also not the channeled thoughts of a disincarnate person, nor is it based on insights gained through artificial or even genuine spiritual experiences. It proceeds directly from Experience, i.e. God-Realization.
In terms of its relevance for this website and its topic, reincarnation, Discourses contains seven chapters on reincarnation and karma, with additional chapters on relevant topics such as "The Nature of the Ego and its Termination" and "The Formation and Function of Sanskaras". This is the clearest treatment of the subject you will find anywhere. It provides a solid and accurate foundation for sifting through the mountain of reincarnation information coming from various other sources. If you see any merit in my articles on reincarnation (that page is linked from the home page of this site), what you are seeing therein is my best interpretation of the teachings in Discourses. My advice is to forget my articles and go to the source.
Note that the version shown above was re-edited after Meher Baba's lifetime, partly to modernize the language and convert it to American English. However, some, including myself, prefer the earlier three-volume set, which is now available online in its entirety. It may also be purchased in print through the same website.
*"Baba told us there are parts of the Bible which are still authentic, like the Sermon on the Mount." Adele Wolkin, as quoted in Glow International, August, 1992.