Segulah for Parnassah- purchase a new Knife on Erev Rosh Hashana

                                                החותך חיים לכל חי

Though this is not a common custom, It is brought down in Seforim to sharpen the knives on erev Rosh Hashana and to buy a new knife as a segulah for Parnassah, There is a discussion among poskim if one may buy a sharp knife it as a gift.

One of the reasons given  is that hashem  in charge of everything, yet He does have a whole slew of ministering angels who carry out His orders."Chatach," (חתך), which means "cut," is the name of the angel in charge of livelihood. Consider that the final letters of the Hebrew words, פותח את ידך, "You open up Your hand"  spell "chatach." Additionally, the word that follows in the verse, "u'masbe'a" – "and satisfy [the desire of every living being]" has the numerical value of 428 – the same value as the word "chatach."
For this reason, purchasing a new, sharp knife is a segulah (spiritually propitious), for livelihood, which we petition from G‑d for the upcoming year. May G‑d inscribe you and your family, and all the Jewish people, for a year abundant in livelihood—and everything good!"Chatach," (חתך), which means "cut," is the name of the angel in charge of livelihood.
For this reason, purchasing a new, sharp knife is a segulah (spiritually propitious), for livelihood, which we petition from G‑d for the upcoming year.
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Nitei Gavriel 11:10