Actions DO speak louder than words.It's just an expression,however,it's not referring to pain tolerance.Of course getting punched in the face is going to hurt,but words only hurt if you let them (as cliche as that may sound).This expression simply means that actions carry a deeper intent than do words.It's very easy to say one thing and then turn around and do the opposite.In time,the actions of a person will tell where they're coming from or what they're up to,more-so than the words that they speak.
Example:A man claims to love his wife but quite often he yells at her,calls her insulting,sometimes obscene names,and sometimes physically abuses her.Now,when he says he loves her,let's say he means it,that it may even be the truth,but the face of things,the reality,does not show love.The actions speak louder because what ever the man says or feels in his heart,his actions dictate everything.The wife best leave him or fear for her life.Another,less dire,situation.A woman says she loves her husband,but never expresses it.There are no spontaneous embraces or kisses.The husband kisses the wife,hugs her,often caresses her,but is lucky to get a return kiss.While this woman can say the words I LOVE YOU 10 times a day on the phone,what do her actions say?The man feels no more loved than the abused wife..