The Tree of Life ironically deals with the topic of death. The film tells you to turn up the sound so you can hear all the first person narration. When their son dies at the age of 19 parents cope with the loss and question their faith, but not severely question their faith that would alter their life style. After the characters are introduced, we still see Sean Penn doesn't own a comb. The film digresses into a Discovery Channel special which condenses the modern version of creation of 14.7 billion years into about 12 minutes. I felt like we had passed into the monolith.
We now start all over with the birth of the children. Hey, we already know one dies. There are things that are whispered. These are meant to be ideas or questions for God. Brad Pitt metaphorically represents the "tough love" God who prepares us for life's journey without us realizing it. Hence we have the macrocosm and microcosm in our tale. One could assume that the microcosm of our life is reflective of our theological views, we carve out a tough love God based upon our tough love "Father". At one point in the movie Brad Pitt insists his son call him "Father" and never "Dad." Having lived in the south, that is a no-no. "Father" is reserved for the heavenly Father. That is a hint of the symbolism. A sermon stresses the book of Job and asks, "Is the scheme of life a fraud?"
Not for everyone. I was very bored until I figured out what they were attempting to do. I think the beauty of the film is that different people can grasp a different meaning from it. It doesn't spell it out. My review is one take.