Mishnah, — Seder Moed, Tractate PesachimChapter 1
“ On the evening of the fourteenth [of Nissan] we check for leavened bread by candlelight. Any place which we do not bring leavened bread into does not require checking. And why did [the sages] say [that we must check up to] two rows in the wine cellar? [It is] a place which we bring leavened bread into. ”
