Ash-Shaykh Abu Ja‘far, may Allah have mercy upon him, says: "Our belief concerning the Tablet and the Pen is that they are two angels."ash-Shaykh al-Mufid, may Allah have mercy upon him, adds that the Tablet is the Book of Almighty Allah in which He has written all that will be till the Day of Resurrection. In the Qur’an we have:
And We have written in the Psalms after the reminder, verily, my righteous servants shall inherit the earth [21:105].
Thus, the Tablet means 'the reminder' (dhikr). 'Pen' isthe name of that thing by whose instrumentality Allah has caused the writing on the Tablet. Hence, Allah has ordained the Tablet to serve as an original record, through which the angels, peace be upon them, acquire the knowledge of what is going to happen concerning what is hidden and what is inspired.
When Allah intended to acquaint the angels with some secret of His, or send a revelation (through them) to one of the prophets, peace be upon them, He commands them to consult the Tablet, and from this they memorize the ordinances which are to be communicated to those to whom they have been sent, and thus they are informed of what they have to do.
This interpretation, more- over, was confirmed by the reports related on the authority of the Prophet and the Imams, peace be upon them all. As for those who maintained that the Tablet and the Pen are two angels, they have indeed deviated from the truth, since angels cannot be called tablets or pens, and since there are no linguistic precedents for an angel or human being called tablet or pen.