en_tn/1ti/05/18.md

For the scripture says

This is personification that means that this is what someone has written in the scriptures. Alternate translation: "For we read in the scriptures that" (See: rc://en/ta/man/jit/figs-personification)

You must not put a muzzle on an ox while it threshes the grain

Paul is using this quotation as a metaphor meaning that church leaders deserve to receive payment from the Christian community for their work. (See: rc://en/ta/man/jit/figs-metaphor)

muzzle

place a sleeve over an animal's snout and mouth to prevent it from eating (See: rc://en/ta/man/jit/translate-unknown)

threshes the grain

An ox "threshes the grain" when it walks on or pulls a heavy object over the cut grain to separate the grain from the stalks. The ox was allowed to eat some of the grain as it worked.

is worthy of

"deserves"