Dear Kathleen,
You are welcome. Actually your posts are always interesting and besides, I have already told you that I deeply enjoy writing, especially when the subject is art, music or literature. So there is nothing to thank me for.
By the way, absorbed in the multiple coincidences, I completely forgot the tree.
Now elaborating a bit more upon 'coincidences': perhaps the fact that both Brueghel and Caravaggio painted such dissimilar versions of a same theme was, after all, not too much of a coincidence. The two of them were almost absolute contemporaries and for all their radically dissimilar styles, which surely responded to the fact that the former was Flemish while the latter was an Italian, the two of them belonged to the Baroque period, which was an Era in which the two almost exclusive subjects of painting in Europe still were the religious and the mythological. For example, if you go to www.Artcyclopedia.com and search for "Rest on the Flight to Egypt", which must have been a favorite theme for artists at the time, you will get no less than sixty responses with works by important painters mainly active from approximately 1500 to 1700.
However, there still remains the fact that YOU had to find all about Jan Brueghel the Elder and his painting PRECISELY NOW in a mystery book which says that the main feature of the painting is the oak tree!
There is a lot to be read about a most special tree in the hermetic and esoteric literatures. That most special tree is perfectly ubiquous, in that it can be at any place where it may be required to be. And wherever that tree is at any given moment, the center of the universe is also there with it. It actually is the Tree of Life which, in different versions, is mentioned in all sacred texts from all religious traditions from all over the world. This tree, in sum, is the "world axis" or axis mundi which traverses in succession the entire chain of worlds and, at the same time, sustains and keeps together the whole universe as a string of pearls. Furthermore, while it remains inmobile, the whole universe revolves around it and would disintegrate if it were not for it. That tree, in fact, is the soul of the universe.
Now it seems that all the artists of the Rennaisense and, most probably, of the Baroque Era were familiar with this tradition, so it would not be at all strange that both Caravaggio and Jan Brueghel the Elder were in fact painting that oak tree as the only one deserving to serve, inasmuch as a representation of the world axis and the center of the universe, as a worthy support for the Virgin and her precious Child when they happened to stop for a nocturnal rest during their flight to Egypt.
I don't know what the book has to say about the tree, or why it is that it constitutes the main feature of the painting according to its author. I only know that thanks to you, it has now become a fascinating matter of thought for me tonight.
Best Wishes,
Luis Miguel Goitizolo