Strong’s Greek
G2407 — hierateuo
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
ἱερατεύω
hierateuo — pronounced hee-er-at-yoo'-o
prolongation from 2409; to be a priest, i.e. perform his functions:--execute the priest's office. see GREEK for 2409
1 occurrence in the KJV.
Luke 1:8
And it came to pass, that while he executed the priest’s office before God in the order of his course,