Abu Hurairah (May Allah be pleased with him) reported:
The Messenger of Allah (ﷺ) said, "He who is asked about knowledge (of religion) and conceals it, will be bridled with a bridle of fire on the Day of Resurrection."[Abu Dawud and At- Tirmidhi]. (FR)
App reference (FR): Book 13, Hadith 15 (FR)
Arabic/English book reference (FR): Book 13, Hadith 1390 (FR)