Tagore, an Indian polymath and proponent of Indian independence, is writing this poem in address to God, "my Father," in the hopes that his country will be permitted to "awake . . . into that heaven of freedom." It is this heaven, then, that Tagore is describing as a place where "the clear stream of reason has not lost its way / Into the dreary desert sand of dead habit." His hope is that the Indian people will be able to see their way into a future uninhibited by the complacency that has come over many of them out of force of habit—the habit being the British rule that had existed in India for all of living memory by the time the Independence movement began to gain force.
Tagore knows that to many of his people, the idea that India is a colony, even a possession, of Great Britain has simply become the way things are, and that this can make it difficult to stir others into action. However, he appeals to the "clear stream of reason" to cut through this complacency as water cuts through sand, rather than getting lost in such an abundance of sand that is "desert[ed]" of reason.