Kendall embraces Reformed theology (after growing up Nazarene). He also believes the gifts of the Holy Spirit are operative today. This may be a surprise because he was trained and ordained in a theological setting that taught him to resist charismatic teaching and experience.
I really like Kendall's book (perhaps because I am Reformed and charismatic). He has written it to (re)introduce us to the Holy Spirit, to show the inconsistency of the teaching of some evangelicals, and to warn of strange fire.
He notes that some Christians emphasize the Word and other the Holy Spirit. He says both are right but the problem is that neither will learn from the other. He desires to see a combination of sound biblical teaching and the encouragement of a greater measure of the Holy Spirit.
Kendall is not naive. He admits there is the counterfeit, "strange fire." He identifies the pitfalls in the charismatic/pentecostal movement and warns against them, such as a defective view of God. He does the same for the Reformed camp, such as cessationism (the idea that miracles ceased when the canon was completed).
He explores what every Christian should know about the Holy Spirit (21 truths). He also writes about Dr. Lloyd-Jones (his predecessor at Westminster Chapel), how to recognize strange fire and what lies behind it, the sensitive nature of the Holy Spirit, his own testimony, cessationism and its consequences, and evidence of the Holy Spirit.
Kendall is open and honest in this book. It is a good look at who the Holy Spirit is, how He is active today, and how that activity is sometimes misunderstood and misused. Any of Reformed theology will find a balanced perspective in this book.