Noah used pitch to waterproof Noah's Ark. Genesis instructs him to coat the ark inside and outside with pitch, creating a seal against water.
The Hebrew term translated as pitch is related to bitumen or another waterproofing substance, but the precise ancient material is debated. Bitumen was widely known in the ancient Near East and could be used for sealing boats and buildings. English translations vary in their wording, including “pitch” and related terms.
The instruction is significant because the ark is presented not merely as a wooden structure but as a vessel prepared to withstand prolonged exposure to floodwater. The passage also specifies gopher wood, compartments, a door, and a window. Although modern artists sometimes depict the ark as brightly painted, Genesis emphasizes its waterproof coating rather than decorative paint.