Bernard of Clairvaux (1090-1153), a French abbot and reformer, was a founder of the Cistercian monastic order. He spent 18 years writing sermons which served as a commentary on the Song of Songs. He died before completing an exposition of the entire book. He only made it through the third verse of Chapter 3 in 86 sermons! Bernard saw the bride in Song of Songs as a representative of both the individual soul and the entire Church; The Bridegroom is, of course, Christ. The book became for him, an allegory of the spiritual life, and more personally his own life with God.
This book is not easy reading, and not for everyone. The copy I have is edited and modernized by Bernard Bangley and is still slow going. I used it as a devotional years ago, reading one small section carefully each day. Here’s an excerpt from the very beginning:
You have studied, denied yourself, and meditated constantly for a long time. I am sure you are prepared for a diet of solid spiritual food. The Song of Songs is tasty bread. Let’s break it and enjoy a substantial meal.
The Song of Songs is a book we don’t often study or spend time with. You might give this book a try and find it well worth the effort.