Who Sin and Death is
Sin and Death stand at the gates of Hell, where Satan encounters them as he sets out toward the new world. Sin appears as a woman above the waist, with serpents below, while Death has no clear form and bears something like a crown.
What Sin and Death wants
Sin and Death long for a home in the new world, and Satan promises them a place there. Sin holds the key given to her by Heaven and opens the gates for Satan against her better judgment.
Sin and Death and the others in the story
Sin springs from Satan's head when he first thinks of rebellion in Heaven, and Death is born from their union. When Satan meets them at the gates, he does not recognise them, showing how far he has already changed.
Their family ties give a visible shape to the way rebellion spreads and produces further harm. Through these figures, Milton presents evil not only as a choice but also as a chain of consequences.
Questions
Who are Sin and Death in Paradise Lost?
They are the two figures guarding Hell's gates when Satan arrives on his journey toward the new world.
How are Sin and Death related to Satan?
Sin is Satan's daughter, and Death is the child of Satan and Sin.
Why does Sin open the gates for Satan?
She opens them because Satan promises a new home for her and Death in the new world.