What you do is all that matters or counts. Saying you did it doesn't count. You need to do something to back up your words. Watching what a person does tells much more about that person than listening to what he or she says. sooo YES!!
it means that what you do shows how you really are. you can say one thing, but it doesn't prove that you mean it. Therefore the way you act shows a lot about your character.
Many languages have expressions similar to the maxim "Actions speak louder than words." ONE of the earliest records of this exact phrase, in English, is: "Actions speak louder than Words, and are...