By: Seyyed Ali Shahbaz
      
“Peace upon you, O Light of Allah in the darkness of the earth. Peace upon you, O Allah’s Intimate Servant. Peace upon you, O Allah’s Argument (over His creature). Peace upon you, O Gateway to Allah. 
“I bear witness that you performed the prayers, defrayed the poor-rate, enjoined the right, forbade the wrong, recited the Book (holy Qur’an) as it should be recited, strove for the sake of Allah exactly as one should strive, (patiently) endured harm for His sake expecting His reward, and served Him sincerely until death came upon you.”
We are still basking in the blessings of the Glorious Eid of Islam by expressing gratitude to God Almighty for His perfection of our faith, completion of His favours, and decreeing of Islam as the religion of all mankind.
Indeed the 18th of Zi’l-Hijjah that went by remains an immortal occasion. It is celebrated for several days, since it was on this day in the year 10 AH at the Ghadeer (pond) of Khum, near Juhfa, the Seal of Messengers, following the express commandment of the Lord Most High, proclaimed his dear cousin and son-in-law, Imam Ali ibn Abi Taleb (AS) as Heir and Master of all and everything after him.
This is firm proof of the fact that leadership in Islam is divinely-decreed. In other words, without designation from the Almighty Creator none can claim to be a rightful Imam. 
This means that except for the 12 Infallible Imams of the Prophet’s Ahl al-Bayt, of whom the Last One is in occultation and will reappear in the end times as Qa’em al-Mahdi (AS) to establish the global government of peace, prosperity and justice, all those who styled themselves as caliphs throughout history were imposters, cheats, and fraudsters.
Glory to God Who has not left the seekers of truth stumbling in the dark and has provided Beacons of Divine Light for our guidance as is evident by the passage from a ziyarah or standard form of salutation to the Prophet’s 7th Infallible Heir that we recited. 
He is none other than “Bab al-Hawa’ej” Granter of Boons or the Gateway to Allah for fulfilment of the deserving needs of the believers. According to a narration, born on Zi’l-Hijjah 20 in Abwa between the holy cities of Mecca and Medina in the year 128 AH (745 AD), he was named Musa in honour of Prophet Moses, by his illustrious father, Imam Ja’far as-Sadeq (AS) – the Reviver of the Prophet’s genuine Sunnah wa Sirah or practice and behaviour.
He was twenty years old when God entrusted him with the divine trust imamate on the martyrdom of his father through poison by Mansour Dawaniqi the self-styled caliph of the Abbasid usurper regime.
A point to note is that like Prophet Joseph he had several older brothers, who were all alive except for the eldest Ismail who predeceased his father. This means Imamate like Prophethood is neither hereditary nor mandatory, and solely depends on Divine Will. 
Imam Sadeq (AS) definitely knew his successor, but in view of political conditions might not publicly announce it, and this was the reason, the tyrant Mansour could not determine and kill the successor of his victim.
The 7th Imam, whose period of Imamate spanned thirty-five years and saw the reign of four Pharaonic caliphs – Mansur, Mahdi al-Abbasi, Hadi al-Abbasi and lecherous tyrant Haroun Rasheed – acquired the epithet of “al-Kazem” which means “Restrainer of anger or emotions”, since he patiently endured hardships upon the Muslims and upon himself, including intermittent bouts of imprisonment.
Nevertheless, he ably guided the ship of Islam through the stormy waters of Abbasid misrule, enlightening all those approaching him for learning the genuine teachings of Islam.
Imam Musa Kazem (AS) held debates with the scholars of other religions, like the Christians and Jews, and convinced many of them of the truthfulness of Islam. 
At the same time, his political acumen prevented many a catastrophe in those crucial days when frequent uprisings occurred against the Abbasids led by several descendants of the Prophet. Examples include establishment of the Idrisid state in what is now Morocco by his distant cousin, Idris, the survivor of the bloodbath of Fakhkh near Mecca, where the Abbasids massacred many of the offspring of Imam Hasan al-Mujtaba (AS). The Imam also remained silent about the uprising of another distant cousin Yahya ibn Abdullah in Tabaristan on the Caspian Sea coast of Iran.
The 7th Imam’s prudence prevailed and was instrumental in preserving the life and dignity of the majority of the followers of the Ahl al-Bayt, to whom he bequeathed bezels of knowledge that have since continued to serve the cause of Islam till this day. 
Imam Musa Kazem (AS), though he was martyred through poisoning in the prison of Baghdad by the tyrant Haroun, he continues to rule the hearts and minds of the seekers of truth from his majestic mausoleum in Kazemayn, Iraq, while there are traces of the graves of the imposter caliphs, let along their palaces.