The poet is describing how he had a hard life. He has encountered many troubles and circumstances, but has never given up even after being pushed up by these evil troubles. After his life has been beaten down, he still feels strong and hopeful. The poet is implying that he has been beaten down, but is still capable and full of strength to conquer the troubles of the life ahead of him.
Now the Author explains that how he differentiates the fact that there will be more circumstances in the future that he cannot prevent from happening. However, the past troubled years has prepared the individual for the future ones. The approaching years must stand and be ready to find the person unafraid and ready to overcome the hardships that the forth comings will provide.
Now the Author explains about how a person is the controller of his own life. Whatever he encounter with such problems or troubles or such circumstances in his life, or whatever life throws at him, he knows that he is the ‘captain of their soul;’ and he can manage his own life. Just like the captain of a ship, he feels that his life is a big ship sailing through the waves of different circumstances and troubles. Life is a struggle and is not absolute.
However, with the authority that he has over his own life, he can proceed on the road of his choice. He is the master of his fate, and the captain of his soul. He is filled with the feeling that he can rule his own life and fight with all worries.