Negative Mitzvah 135
A Priest who is not circumcised is forbidden to eat "Terumah"
Leviticus 22:10 "A tenant of the priest or a hired servant may not eat of the holy [food]"
Circumcision is the most important sign of a male's connection to HaShem. Without circumcision, the male lacks that special bond.
A non-circumcised priest may not eat "Terumah." He also is forbidden to eat other sacrificial meat.
Negative Mitzvah 136
An impure Priest is forbidden to eat "Terumah"
Leviticus 22:4 "Any man who is of the seed of Aaron...shall not eat of the holy [food]s, until he is pure"
A priest who has become impure may not eat from Terumah.
He must first purify himself according to the Torah's instructions and he is then allowed to eat his Terumah.