" When Obedience becomes our goal, it is no longer an irritation; instead of a stumbling block, it becomes a building block."

What i think this quote means is once you have obedience you wont have to deal with it bothering you in life. It was once a thing you stumble on but now its something you can use to build upwards. Once you have obedience that can help you make new things in your life. It is a block that can help you achieve your goal in life. It is a block step forward.