תּוֹשָׁ֥ב וְשָׂכִ֖יר לֹא־יֹ֥אכַל־בּֽוֹ׃
거류인과 타국 품꾼은 먹지 못하리라
Shenei Luchot HaBerit
Commandment 282 forbids an uncircumcised priest to eat תרומה. The Talmud Yevamot 70 derives this law by association with the law prohibiting any non-circumcised Jew to eat from the Passover sacrifice. Since that prohibition extends to the resident stranger and the hired hand, so does this prohibition extend to the hired hand of a priest.