The sinner’s minchah-offering, as well as any other minchah-offering, whose kemitzah was performed by a non-Kohen, [or] an onein, [or] a tevul yom, [or] who lacks vestments, [or] who lacks atonement, [or] whose hands and feet have not been washed, [or] who is uncircumcised, [or] who is tamei, [or] who is sitting, [or] standing upon utensils, [or] an animal, [or] on his colleague’s feet — is invalid. [If] one performed kemitzah with the left hand, he has invalidated [it]. Ben Beseira says: He should replace [it] and perform kemitzah again with the right hand. [If] he performed kemitzah, and a pebble came into his hand, or a grain of salt, or a particle of frankincense, he has invalidated [it]. Because they said: The kometz which is excessive or deficient is invalid. Which is excessive ? [One in which] he removed a heaped kometz. [Which is] deficient? [One in which] he performed kemitzah with his fingertips. How does he do [it]? He extends his fingers over the palm of his hand.