It is narrated from Sayyiduna Talq bin Ali (may Allah be pleased with him), and he was among the delegation that came to the Messenger of Allah (peace and blessings be upon him), that the Messenger of Allah (peace and blessings be upon him) said: "Whoever is asked about some knowledge and conceals it will be bridled with a bridle of fire on the Day of Resurrection."
Hadith Referenceالمعجم الكبير للطبراني / باب الطاء / 8220