We cannot always be on the mountain, isolated from our world and the tasks that need to be done. To be true missionaries of Christ, we are tasked to go out into the sea of our turbulent society that challenges and rocks us, threatening to overwhelm and drown us despite the boat of faith that we have constructed. Jesus shows the disciples that they can overcome those waves even without that human-constructed boat as long as they keep their eyes on Him. This is not an easy task, and even Peter finds himself faltering and failing, but again, Jesus saves him the moment that Peter asks for His help.
Jesus did not command His disciples to stay on the mountain forever. In fact, Peter was ignored in last week's Gospel when he asked to make a more permanent residence on the mountain. Rather, He tells them time and again to go out onto the water, and He meets them there. From the beginning, God reached into the waves to bring stability to chaos. We have been tasked to do the same.