Practical Elemental Magick: Working the Magick of Air Fire Water & Earth in the Western Esoteric Tradition, by David Rankine and Sorita d'Este is a great book to buy! If you are new to elemental magic you will understand the very basics you need to know. It is very useful and educational. If you are more advanced you will find useful details and practical knowledge. This book fills many gaps if you have read other books and if not, it gives a general and more detailed knowledge leaving no questions as a whole.
The book is beautifully categorized containing small chapters making it easy to read as it is small having 188 pages. This characteristic makes it easy to read by anyone even by those who have very strict and limited program and still want to learn more about elemental magic. However, the practices need time and someone must be willing to give time to the practical part!
In this book, you can find theoretical information for the four elements and a lot of tables about colors, names, planets, tools, archangels, signs, deities, axioms, seasons, qualities, creatures that will help you practically while performing your rituals about what element to use according to your purpose. There are different chapters about the elemental archangels and beings. There are meditations about the four elements that help you explore each one separately. There are chapters about the magical tools, elemental temples, basic rituals such as the magic circle, consecration of the tools while also providing the preparation of the ritual and other.
Τhe writers have great knowledge of the Hellenic history putting forward ancient texts and writers. They also give sources of other great and important information including Qabalah and the Grimoire Tradition. This book provides the reader with researched information and perspective.
If you buy this book as a starter, make sure that you will re-read it after some years. Don't leave it on the shelf because you read it once. While you will be evolving in your magical practices and techniques it is absolutely sure that after re-reading it, you will discover new things to learn and add to your practices. As I wrote above, this book is both for the beginners and more advanced practitioners as everyone can find different information according to their practices and needs.
Theurgy and Philosophy are two different methods which lead to the union with God.