Has the Force ever acted on its own or as a deity in Star Wars canon?
According to this answer by DavRob60 on the question of Anakin's father.
There is a recently published book, Star Wars: Darth Plagueis, that supposedly answer this question. From Anakin Skywalker Wookieepedia article
In addition, although Darth Plagueis did attempt to influence the midichlorians to create the ultimate Sith weapon alongside Darth Sidious, the experiment was ultimately a failure, and the midichlorians, sensing the Sith's inherent malevolent intention, not only refused to do so, but in retaliation, conceived Anakin Skywalker in order to destroy the Sith once and for all.
It appears that the force (or at least the midi-chlorains) acted in a Deity-like fashion to create Anakin Skywalker.
The force is a mystical energy field that surrounds everything and everyone in the universe. It has no consciousness and takes no action.
The force is more like a force of nature than a diety.
Therefore the Jedi/Sith and all other force sensitive beings who try to understand it are less like priests and more like researchers, but due to the metaphysic nature of the force doing so requires a spiritual mindset.