What does 2 Kings 10:23 mean?

Jehu and Jehonadab went into Baal’s temple. Jehu said to the worshipers, 'Look around and make sure there are no servants of the Lord here—only Baal worshipers.' 2 Kings 10:23 - Modern Text Bible

(Jehu double-checks that only Baal’s followers are present, so no worshipers of the Lord are caught in the massacre.)