Another possible source text for Tree of Life?

Probably not.  Nevertheless, the similarities and parallels struck me immediately.  If you've seen it, you'll probably notice them as well.  The whole chapter is equally beautiful and brilliant--heck, so's the whole book--but here's the important passage, where he describes the change that came over Francis at his conversion, and his evolution into both a saint and a poet:

     So arises out of this almost nihilistic abyss the noble thing that is called Praise; which no one will ever understand while he identifies it as nature worship or pantheistic optimism.  When we say that a poet praises the whole creation, we commonly mean only that he praises the whole cosmos.  But this sort of poet does really praise creation, in the sense of the act of creation.  He praises the passage or transition from nonentity to entity; there falls here also the shadow of that archetypal image of the bridge, which has given to the priest his ancient and mysterious name.  The mystic who passes through the moment when there is nothing but God does in some sense behold the beginningless beginnings in which there was really nothing else.  He not only appreciates everything but the nothing of which everything was made.  In a fashion he endures and answers even the earthquake irony of the Book of Job; in some sense he is there when the foundations of the world are laid, with the morning stars singing together and the sons of God shouting for joy.  

--G. K. Chesterton,  St. Francis of Assisi

Note: The Latin for priest is pontifex, which has its root in pons, pontis, n. --bridge.