"If they disobey you," meaning: the polytheists, "say: 'Indeed, I am free from what you do.'"
﴿فَإِن عصوك﴾ يَعْنِي: الْمُشْركين ﴿فَقل إِنِّي برِئ مِمَّا تَعْمَلُونَ﴾.