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

This quote means that you need to set goals in life and accomplish them. For example, you will have to obey to accomplish your goal. If you do not accomplish your goal then you will go down and not accomplish your goal. Some situations are not to drink alcohol and not do do drugs some people fail their goal and go stumbling down your pyramid. And others that accomplish their goal they go closer and closer reaching their goals.