The book is based on Jonathan Edwards' personal experience as a pastor and preacher of the Gospel. He witnessed the conversion of a very large number of people to God who were confident of the forgiveness of their sins. However, Edwards discovered that as time passed, many of these people returned to their previous sinful lives. He began to speculate about the cause of this phenomenon and came to the conclusion that people were deceived by Satan, who imitates the work of God to deceive them more successfully (1 John 4:1). And in this book Jonathan Edwards shows the difference between the work of the Spirit of Truth and the spirit of error. Particular attention is paid to the question: how to recognize the work of the Spirit of God? He speaks in detail about the actions of the Holy Spirit in the human soul, such as consciousness of sinfulness, turning to God, faith and its fruits.