Where lipstick is concerned, the important thing is not color, but to accept God's final word on where your lips end.

Framed as mock-serious advice, the line satirizes cosmetic culture by treating the natural boundary of the lips as a kind of divine decree. The humor comes from the exaggerated moral/theological language (“God’s final word”) applied to a trivial, everyday practice—overlining lips with lipstick. Implicitly, it pokes fun at the anxiety around appearance and the belief that beauty can be engineered past physical limits. Like much of Seinfeld’s observational comedy, it elevates a mundane detail into a grand principle, exposing how people rationalize small vanities with outsized seriousness.