An “Act of God” is a situation where injuries or property damage occurs, like damage caused by a tree falling, not through the negligence of another person.
Let’s use as an example a tree that fell on a house that someone was renting. If it was an aging tree that was leaning for years and the landlord knew that the old tree was a problem and they didn’t do anything about it, this may not fall under the category of “Act of God” because the landlord may have been negligent in not removing the tree before it fell.
But if it was a quick occurrence and a healthy tree, that may be something completely different. For example, recently here in Reno, Nevada, we had an occurrence in the fall season where there were still leaves on the deciduous trees, and there was a big, wet snowstorm. Water stuck on those leaves and caused a lot of damage by causing the branches around town on those trees to fall. That is an “Act of God.” It has nothing to do with knowledge that the trees were in bad shape. All of these trees were fine before the ice storm. Reno just happened to have an extraordinary snowstorm before the leaves had fallen off the trees, and the weight of the snow on those leaves caused those branches to fall. If one of those branches fell and hit your car or hit you that would be an “Act of God” because it would really be no fault of another individual.