Majma al-Zawaid — Hadith 782

Sayyiduna Ma'qil bin Yasar (may Allah be pleased with him) said: I heard the Prophet (peace and blessings be upon him) say: "Act upon the Qur'an! Treat as lawful what it makes lawful, treat as unlawful what it makes unlawful, follow it, and do not deny anything of it. Whatever seems ambiguous to you, refer it to Allah Almighty and to those in authority after me, so that they may inform you about it. Believe in the Torah, the Gospel, the Psalms and whatever the Prophets were given by their Lord. May the Qur'an and the clear explanation it contains cure you, for it (the Qur'an) is an intercessor whose intercession will be accepted, and an advocate whose word will be believed. Each of its verses contains light until the Day of Resurrection. I was given Surah al-Baqarah from the Dhikr; I was given Surah Ta Ha and Surah al-Tur from the Tablets of Sayyiduna Musa (peace be upon him); I was given Surah al-Fatihah and the closing verses of Surah al-Baqarah from a treasure beneath the Throne; and I was given the Mufassal as an extra." Al-Tabarani recorded it in al-Mu'jam al-Kabir, and in one of his narrations the wording is: "Whatever doubt you have about it, ask the people of knowledge about it and they will tell you."
This narration has two chains: one of them contains Abdullah bin Abi Humayd, and the hadith scholars are agreed that he is da'if (weak); the other contains Imran al-Qattan, whom Ibn Hibban mentioned in Kitab al-Thiqat, while the rest declared him da'if (weak).