John Milton's "On His Blindness" is an English sonnet about a man who surrenders himself to the will of God. In it, Milton confesses that midway through his life, he has been rendered blind and suffers great personal grief to the point that his only hope is in the mercy of God. In many ways, this poem is an allegory, in that Milton uses his story to represent universal plight and struggling among mankind.
Milton also utilizes personification in this sonnet. He turns "patience" into a being that he can speak to, and that can bring him salvation.
This is an autobiographical meditation inward, in which the Petrarchan sonnet format typically used to write about love is instead employed to write about suffering and redemption. It was written in 1655, a few years after Milton became completely blind. He believes that his blindness came through his labor, and that his labor was for God. This is vital, because Milton emphasizes in the piece that God judges man by the work he does for Him. One famous line in the poem that underscores his value of servitude is Milton's statement, "They also serve who only stand and wait."
Although he bemoaned his failing eyesight, Milton wrote two of his greatest works, "Paradise Lost" and "Paradise Regained," after he became blind.