[Sacks]

Ask the owner if he will introduce you to the dog and tell it you are ok. He sounds like an asshole so he probably won't. Next time you feed the dog use a firm voice and tell it to sit or stay and don't give it the food until it complies. Hold your hand up, this is what people usually do to teach things to sit. ALWAYS LOOK IN IT'S EYES and never look away. Also every time it barks or lunges yell "NO" in a very commanding voice and never run or fidget or anything. Point at it when you say no and stand there. Say it 2 or three times or until it stops. If you're really manly and bold or it's a dog that is not so dangerous, every time a dog does not respect you and keeps up with bad behavior flip it over on it's back and stare in it's eyes until it looks away. Do this as many times as you need to to establish that you are alpha.