Dr. Mariottini wrote:
One of the greatest teachings of the Old Testament is that the God of Israel desires to have a personal relationship with his people. In his desire to establish a relationship with humanity, God does not always wait for people to come to him.
Rather, God takes the initiative and reveals himself to humanity. This manifestation of God is commonly known as a theophany. The Old Testament contains many stories demonstrating God’s immense love for his creation and the extent to which he is willing to go in order to bring human beings into fellowship with himself.
This article does an awesome job in explaining the over-arching theme of the Bible.
Dr. Claude Mariottini - Professor of Old Testament: The Manifestation of God in the Old Testament