10 so that you can distinguish between the holy and the common, between the unclean and the clean,

Read Leviticus 10:10 Using Other Translations

And that ye may put difference between holy and unholy, and between unclean and clean;
You are to distinguish between the holy and the common, and between the unclean and the clean,
You must distinguish between what is sacred and what is common, between what is ceremonially unclean and what is clean.