Do What You Can

There is the belief among rabbis that by performing mitzvot, one would be actively participating in Tikkun Olam (crafting a better world). With this in mind, it is difficult for any person to do all the 613 mitzvot all of the time.  Therefore many rabbis specialized in mitzvot and made this their forte.  There is the passage in the Torah which states that you must help your neighbor's afflicted animal.  Taking this portion a rabbi long ago, used to travel around and look for animals in distress, just to help them.