The way of the Jedi is to live in harmony with The Force.
You can believe that The Force is God, a force of nature, a scientific phenomenon, or whatever. It is inconsequential. The Force is. It does not judge who uses it or what you may believe about it. The Force does not judge you, though those with whom you interact may.
This is the “Light side/Dark side” dichotomy.
Light or dark side, The Force is the same. As mostly beneficial beings, we seek to walk on the Light Side. We choose how we use The Force. The Jedi choose to use it for good causes.
The universe is dark. Darkness is the absence of light. As Jedi, we choose to create Light rather than remaining in the darkness. The Jedi choose the Light side. We choose to make a positive difference in the world.
The Force manifests in three ways: the Unifying Force, the Living Force, and the Personal Force.
The Personal Force is how it manifests in each individual. Each individual is unique and thus will tap into The Force in different ways. The Force also effects each individual in unique ways. To learn to make use of the Personal Force, a Jedi practices introspective meditation, observation, and continual self-improvement. Thus a Jedi can utilize The Force in him or her own self.
The Living Force is the force of Life itself. Through mastery of the Living Force, a Jedi can sense the health of a living thing and make changes to heal it. This is the manifestation of The Force that allows a Jedi to communicate with beings who’s language he may not know or who may not even have a formalized tongue. It is what gives the ability to seemingly read minds or control the thoughts or actions of other living things. The Jedi learn to tap the Living force through application of the Personal Force to biology, physiology, medicine, psychology, martial arts, and similar studies.
The Unifying Force is the manifestation of The Force which ties all things together. Time and space are how we perceive the Unifying Force. Through our knowledge of the Unifying Force, Jedi can sense the way things happen, the interaction between things, people, groups, objects, and time.
By careful study and practice, a Jedi comes to be in harmony with The Force. To an extent, he can control it. To an extent it can use him as an instrument. When in harmony with The Force, a Jedi becomes a powerful and beneficial being.