وَجَاءَتْ كُلُّ نَفْسٍ مَعَهَا سَائِقٌ وَشَهِيدٌ.
And every soul shall come, with it a driver and a witness. (Sura Qaf 50:21)
Shaykh Tusi has said that there are three statements regarding their being witness: The first is that they are witness over people in the matter of their deeds in this world and in the hereafter which might have been done against truth has been said:
and the prophets and the witnesses shall be brought up. (Sura Zumar 39:69)
Secondly, it may mean that you are proof (Hujjat) on people so put before them the truth and the religion and the messenger may be witness over you and may put (describe) the truth and religion.
Thirdly, these noble ones will give witness about the messengers that they conveyed the Divine Commands and that their communities belied them, and that the meaning of the messengers being witness over them is that they will give witness about their deeds or will be proofs over them or will give witness about them on the Day of Judgment that they had given true testimony. In this case upon would be in the meaning of for, that is, upon you will mean for you.1
Kulaini, Saffar, Ibne Shahr Aashob and Ayyashi have, with reliable chains of narrators, quoted Imams Baqir and Sadiq (a.s.) that they have while explaining this verse they said: We are the medium nation (Ummate Wusta) and we are Allahs witness over the creation and Allahs proof (Hujjat) on the earth.
Furat has, with reliable chains of narrators, about the meaning of this verse, quot