What is the Book of Al-Jafr, who wrote it, and is it permissible for a Muslim to read it and act upon what is in it?

The book "Al-Jafr" is a book of falsehood and slander, claiming knowledge of the unseen. The Shiites sometimes attribute it to Ali ibn Abi Talib, may Allah be pleased with him, and sometimes to Ja'far ibn Muhammad al-Sadiq, may Allah have mercy on him, claiming that it is written on goatskin. This is a lie from the lies of the Rafidah (rejecters), and Ali, may Allah be pleased with him, denied the existence of any revelation with them except what is in the Book of Allah and what is in the Sahifah (scroll). Scholars have affirmed that everything attributed to Ali or the Ahl al-Bayt (People of the House) that they were distinguished by special knowledge unique to them is a lie.