To Bark or To Bite

i entered a home. No one was in the porch. i headed to the main door but the sight of the dog (i's familiar with) stopped me to think before leaping. A motorbike stood like destiny between the two - me and the ferocious German Sheppard dog. The dog turned on the other side, i though it was leaving. It only took a second to realize that it was trying to come over to get my calcium deprived bones. Terrain was such that if i tried to run towards the main door, i'd be in trouble. Hence, i turned back towards the gate. I didn't just turn my back - i ran like an athlete starts a 100m sprint in Olympics. Just before reaching the doorknob i looked back to be aware of the situation and to my vehshat (fear) the dog was madly jumping and running towards me. Those moments between my opening the knob, getting out and sighting the vicious dog were very . . . dreamlike exciting xD because i knew i'd make it...

Pitrus Bukhari, an Urdu writer and MA English, makes a point about this assertion that barking dogs don't bite: how do you know when they stop barking and start biting?