Having a leader and a guide who draws people nearer to righteousness is a blessing and grace of God. The concept of Imamate in Shi‘i Islam deems it necessary to have a guide who will lead the Muslim society after the Prophet’s death by presenting true Islam as well as being a political leader. This guide is appointed by God and possesses qualities of piety, knowledge, wisdom, and infallibility. Part IV of this series verified that the Shi ‘a understanding of Imamate is compatible with the Qur’an in that God refers to Himself as having rule, governance, sovereignty, and the power to choose, and people are asked to obey Him, the Prophet, and those “vested with authority among the people” (i.e. the infallibles). This part studies the group of verses that refer to the profound concept of witness, including his roles and qualities. According to these verses, there must be a witness amongst every generation of people. The Qur’an indicates that the witness who followed Prophet Muhammad (s) was from him and had knowledge of the Book; these qualities can only be found in Imam Ali (a).