At first the painting appears to be of a husband and wife at home, but there are some subtle clues that this woman is the man’s mistress and that she is kept in this domestic space: she wears no wedding ring, the cat toys with a mouse, the clock is under glass, and the fact that the room is decorated in a gaudy nouveau riche style not suitable for a Victorian lady of class. The mirror on the wall behind the couple reveals that the woman is looking out a window situated just behind us viewers. She appears to have just realized something and is in the moment of getting up off the man’s lap, to his dismay. She sees the light, as the title suggests.
The painting is believed to be the companion piece to another Hunt painting titled The Light of the World, in which Jesus holds a lantern and knocks on a door with no handle. Hunt said that the door represents “the obstinately shut mind.” When viewing the paintings together, it’s easy to see how the woman hears Jesus’ knock and gets up to answer it. Perhaps she will leave this philandering man and start a new, virtuous life.