In the Genesis flood account, Noah was told to take seven pairs of clean animals.
Genesis 7:2 distinguishes between clean and unclean animals. It instructs Noah to take seven pairs of every clean animal, while unclean animals are represented by one pair. Genesis 7:3 similarly gives seven pairs of birds.
This passage is often remembered only as an instruction to take two of every animal. That simplified phrase reflects the general ark image, but the detailed Genesis wording includes a different number for clean animals and birds.
The distinction also connects with later biblical dietary and sacrificial laws. After leaving the ark, Noah builds an altar and sacrifices some clean animals, which helps explain why the narrative gives a larger number for that category.