Rabbi David Aaron is a non-dualistic, panentheistic Jew --- this is the belief that the world is part, though not all of God. This notion is reflected in all of his writings.
His most common metaphor of the individual human connection with God is God as the sun and people and reality as its rays. We are not the sun, but we are also not detached from the sun.
In such a view, God is the root of all existence. Or stated in more extreme terms, everything shares some vital essence with God, and therefore, everything is God.
In Inviting God In, Rabbi Aaron examines the Jewish holidays in light of this view. He has some interesting things to say about some standard notions.
He equates Rosh Hashanah with the idea of monotheism --- one God who sits in judgment of the world and separate from the world. Yom Kippur is the day when God presents God’s true nature, the panentheistic view.
Rabbi Aaron also gives special importance to Purim, which he connects with Yom Kippur. Purim is a minor holiday, dismissed by most as a children's holiday, but for Aaron, it is a taste of the World to Come, when distinctions between good and evil, right and wrong, will melt away, and we will all see ourselves as we truly are, a part of God.
Inviting God In is by turns hokey and profound, which is Rabbi Aaron’s style. But there is much good to glean from his teachings. A view of the world, God and people that is both attractive and hits a poetic chord in the heart.