What is the ruling on one who mocks Islam through joking, and must he re-embrace Islam if his act is considered apostasy?

Mocking Islam or its rulings is an act of disbelief that expels one from the faith, whether done seriously or in jest, as Allah Almighty says: "Say, 'Is it Allah and His verses and His Messenger that you were mocking?' Make no excuse; you have disbelieved after your belief." Jestingly committing disbelief is disbelief, and there is no disagreement on this matter. Whoever does this, being sane and uncoerced, has apostatized from Islam. They must offer sincere repentance to Allah Almighty, for Allah accepts sincere repentance and transforms evil deeds into good ones.