Repent, the kingdom of God is near.
Where there is law, there is sin and where there is sin, there is the salary that is death. Man, by his disobedience, broke his covenant with God. This created a barrier in his relationship with God.
As the Lord God is compassionate God, He does not please in the death of the wicked, but He wants him to repent and have eternal life. He says it in his word: "God loved the world so much that He gave His only Son so that anyone who believes may not perish but have eternal life" (John 3:16).
To restore this relationship torn because of the sin, God turns towards the man He had created in his own image and according to his likeness. He gave him the way to encounter Him, the way of repentance. It's all the author recalls in this book the immensity of God's love in these times of the end that precede the return of Jesus Christ. He talks about it in detail so that everyone can review their lives and embark on the path of salvation.