Passover is a holiday that mandates our complete involvement, not just during its eight days but for weeks before. Aside from the regular holiday obligations, we are also commanded (Exodus 13:3–7): “No leaven shall be eaten . . . For seven days you shall eat unleavened bread . . . and no leaven shall be seen of yours [in your possession].”
We accomplish this by cleaning and inspecting our homes well before Passover, and gradually eliminating chametz from every room and crevice. This intensive cleaning takes place in Jewish homes throughout the world.