'Serving' in the Bible

He is to stay in that city until he stands trial before the assembly and until the death of the high priest serving at that time. Then the one who committed manslaughter may return home to his own city from which he fled.”

instead, it [is] a witness between us and you, and between our generations after us for performing the serving of Yahweh in his presence with our burnt offerings, sacrifices, and fellowship offerings; so that your children may not say in the future to our children, "You have no portion in Yahweh." '