Chametz

The First Passover Meal
by the Self-realised painter Chagall

The Torah states that one must remove all unleavened bread (chametz) from one's possession before Passover.

"the reference is to nullifying it in one's mind, to considering it as dust, and as being no longer in one's possession. One must consciously consider all of the chametz that is in one's possession as if it were as useless and worthless as dust. By nullifying one's chametz in one's mind and considering it as being no more than dust, and thus ownerless, one fulfills the mitzvah of removing chametz from one's possession... The prohibition does not apply to chametz which is either ownerless or which belongs to someone else."
- Eliyahu Kitov

Similarly, disownership of thought is a means of nullifying it and rendering oneself fit for the Passover of the Supreme Self.