When Lilith fled from Eden, she didn't just have the Word of God- her first and only daughter Sophia was growing inside of her. Sophia still carries the scar from the angel's attack on her mother, but unlike Lilith, she care bear daughters as well as sons. Sophia can be the beginning of a race of superhumans, and she is the only other living creature that can pronounce Lilith's potent Word of God. It is for these reasons that Lilith has kept her locked away for thousands of years.
That is, until the day Sam's misadventures set her free. Sophia has been waiting milleniums for this- now it is her chance to raise some hell!