Life, in the simplest terms, is a process going from a high energy state to a low energy state. When a process reaches equilibrium and stops, it is dead.

Water and fire could not possibly be considered living beings under the modern definition of life, but they are greatly analogous to the processes that maintain life.

Metabolism maintains cells alive via the flow of protons inside a proton gradient and the controlled combustion of carbohydrates, processes that are identical to water flowing and fire burning.

Rather than saying that anything that flows or burns is alive, or that anything that goes from a high energy state to a low energy state is alive, it is more accurate to say that any system that contains an energy gradient will produce work as the system reaches equilibrium, and the work can be leveraged to sustain life.