Abu Imran al-Jawni relates that it is narrated from Sayyiduna Jundub (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever speaks about the Qur'an according to his own opinion, even if he says what is correct, he has still erred."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1659