כי שכר הוא לכם חלף עבדתכם באוהל מועד
The Torah describes the Maaser, tithe, which is given to the Levi as payment for the service Hashem requires them to perform. Nothing is innately holy about wages. This applies across the board to all matnos Kehunah, gifts given to the Kohanim, and matnos Leviyah, gifts given to the Leviim, which are all considered payment for their service. The Sefer Yagdil Torah quotes the Ohr Sameach who questions this halachah. The Kohanim receive a number of matanos, gifts: Terumah, Terumas Maaser, Pidyon HaBen, etc. A Kohen does not have to be actively involved in sacred service in the Sanctuary to…