Muslim bin Makhshi (may Allah have mercy on him) narrates from al-Firasi, from his father (may Allah be pleased with him), that he said to the Messenger of Allah (peace and blessings be upon him): "May I ask (people)?" He (peace and blessings be upon him) said: "No; but if you must ask, then ask the righteous."
The hadith of Sayyiduna Qabisah bin Mukhariq (may Allah be pleased with him) and other hadiths about whom asking is permitted for and whom it is not permitted for have their place in the Book of the Division of Charities.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7878