Is he who described the beard as "filth" an apostate, knowing that he prays supererogatory prayers and did not intend to diminish the Sunnah?

Whoever mocks the beard, knowing it is a Prophetic Sunnah, his action is grave, and there is a fear for him of apostasy from Islam, due to the Almighty's saying: "Say, 'Is it Allah and His verses and His Messenger that you were mocking?' Make no excuse; you have disbelieved after your belief." However, if he was ignorant of it being a Sunnah, then it is conceivable that he does not intend to belittle the Sunnah.