Benjamin Lay (1682–1759) was a Quaker philanthropist and abolitionist.

His passionate enmity of slavery fueled by his Quaker beliefs, Lay made several dramatic demonstrations against the practice, the most notable at the 1738 Philadelphia Yearly Meeting of Quakers. Dressed as a soldier, he concluded a diatribe against slavery by plunging a sword into a Bible containing a bladder of blood-red pokeberry juice, which spattered over those nearby.