Redemption Song is a call for rebellion, not necessarily against the enemies outside, but the enemies within. His rebellion, the mental rebellion, is being strengthened by religion, and the belief in the Almighty. He says, even though he had been thrown into slavery physically, “My hand was made strong, by the hand of the Almighty” and triumphantly looks forward towards the future. Despite relying on God for strength, Marley says that one’s mind is supreme. “None but ourselves can free our minds.”
Even though a slave is said to be the owner of his master, no one can own the mind of even a slave. How much you are a slave physically, you can be extremely free mentally. Also no one can stop a slave from singing freedom songs, the only thing he has. Freedom is a concept, a longing and a hope a slave would have. But it is something even a slave can own, if the mind is free.
Marley says that “all I ever have” are redemption songs. By saying “ever” he might be saying that whether you are slave or a free man, you are ultimately a slave of the system. The system is being driven by a few who suppress and oppress the masses. The masses can have only the freedom of the mind, whether slave or not. In that sense, Redemption Song seems to be a call for rebellion of non violent solidarity against the oppressive system.