examples of mutual aid would include service workers pooling resources (money. shelter. labour.) to help each other get through the lack of work, or recovered patients donating resources back into the system to help the next wave of sick people.

and, there's a concept of mutualism attached to helping your parents or grandparents or other relatives, who raised you and fed you as children. 

but, "random acts of kindness" are not mutual aid and should not be confused for it. that's an abuse of the language that needs to be corrected immediately. anarchism will collapse under any kind of kantian system of ethics; it's not sustainable. and, i'd argue it isn't desirable, either.

this is one of the differences between christianity and socialism.