In the Genesis story of Noah’s Ark, pitch sealed the vessel inside and outside.
Genesis 6:14 tells Noah to coat the ark with pitch on both its interior and exterior surfaces. Pitch is a thick, water-resistant substance traditionally associated with tar, resin, or bituminous material. In the biblical setting, the instruction functions as practical waterproofing for a wooden vessel.
Translations differ slightly in wording. Some use “pitch,” while others use terms such as “tar” or “bitumen,” reflecting difficulties in mapping ancient material vocabulary onto modern English. The answer expected from the familiar English wording is pitch.
This detail is sometimes confused with the ark’s construction material. Gopher wood is the material named for the structure, while pitch is the coating intended to make it watertight. Genesis does not say that pitch was used as the wood itself, nor does it identify a precise geological source for the substance.