"The Messenger of Allah said: 'When the last people of this Ummah curse the first, (at that time) whoever conceals a Hadith will be concealing what Allah has revealed.'" (Maudu') (Using translation from Ibn Mājah 263)
"إذَا لَعَنَ آخِرُ هَذه الأمّةِ أوَّلهَا، فَمَنْ كتمَ حديثًا فقد كفر بما أَنْزَلَ الله" (فقد كتم ما أنزل الله).