The word jubilee is derived from the Hebrew yobel, meaning ram's horn. In the ancient time, the jubilee was announced by the blowing of the shofar, a trumpet of ram's horn, and as a result, the occasion came to be known as yobel, or jubilee. The Arabic word for jubilee is also yobel, and Turkish ellinci. Jubilee is a momentous occasion, denoting the celebration of a period of time, anniversary or other special occasions.

A peep into the historical records tends to reveal the culture of holding the jubilee festival which was celebrated for the first time by Moses in obedience to the commands of religion before the inauguration of the Christian era. The Law of Moses prescribed a special year for the Jewish people: "You shall hallow the fiftieth year and proclaim the liberty throughout the land, to all its inhabitants; it shall be a jubilee for you when each of you shall return to his property and each of you shall return to his family. This fiftieth year is to be a jubilee year for you: you will not sow, you will not harvest the un-gathered corn, you will not gather the untrimmed vine. The jubilee is to be a holy thing to you, you will eat what comes from the fields." (The Book of Leviticus 25, 10-14) The trumpet with which this particular year was announced was a goat's horn called yobel in Hebrew, and the origin of the word jubilee. The celebration of this year also included the restitution of land to the original owners, the remission of debts, the liberation of slaves and the land was left fallow. In the New Testament, Jesus presents himself as the One who brings the old Jubilee to completion, because he has come to "preach the year of the Lord's favour" (Isaiah 61: 1-2).

The jubilee was instituted by Pope Boniface VI, who granted on February 22, 1300, and for each 100th year to come. In 1343, Clement VI set a period of 50 years between the jubilees. Later, Pope Urban VI decided in 1389 to reduce the cycle to 33 years in memory of the age of Jesus. In 1470, Pope Paul II fixed the jubilee for every 25 years.

The sources produce a heap of evidences that the Mughal emperor Akbar was weighed in the gold in an open plain, decorated with jewels. The scale was made of gold, wherein the throne of gold was placed. Before that the emperor was weighed against seven kinds of grain, coral and gold on the occasion of Navroz. Sir Thomas Roe writes that emperor Jhangir was also weighed against gold, and his weight was reported about 130 pounds. Emperor Aurengzeb was not only weighed once against gold, but also against silver, grains and the bottles of perfumes. Situ, the king of Burma had weighed his son against gold. King Sajdrish was also weighed alike. Govind Chandra, the king of Kanoj was also weighed against gold when he defeated Changthuwar in 1810. King Changthuawar attacked in the plains of Ganges, where he was weighed in gold in his camp and distributed it in charity. In 1870, the king of Travankar was also weighed in gold. Sir Sayajrav, the king of Gaikwad was also weighed against gold and also Bhagavat Shin, the king of Gondal state of Kathiawar was weighed in gold in 1944, and when he was to be weighed in diamonds, his death took place. But, any instance where a religious head had initiated the ceremony of getting himself weighed against gold, diamonds and platinum has not, so far, been brought to light. During the course of history of spiritual magnates extending over a period of 1400 years, there is no episode disclosed when the followers of any spiritual head had ever achieved an honour of intrinsic devotion except Imam Sultan Muhammad Shah. The celebration of his jubilees afforded to the Ismaili world a unique opportunity of demonstrating their deep rooted affection and fidelity for their spiritual father.

In the general usage, a jubilee is marked by an anniversary, such as silver (25 years), golden (50 years), or diamond (60 or 75 years). Imam Sultan Muhammad Shah became unique in the world history, who had been weighed on every anniversary against gold, diamonds and platinum.

While examining the Ismaili history, it appears that the following Imams had completed the glorious period of their Imamate for 25 years and above :-

1. Imam Ali bin Abu Talib (632-661) : 29 years
2. Imam Zayn al-Abidin (680-713) : 33 years
3. Imam Jafar Sadik (733-765) : 32 years
4. Imam Muhammad b. Ismail (775-813) : 38 years
5. Imam Razi Abdullah (840-881) : 41 years
6. Imam Hakim bi Amrillah (996-1021) : 25 years
7. Imam Hadi bin Nizar (1097-1136) : 39 years
8. Imam Ala Muhammad (1166-1210) : 44 years
9. Imam Alauddin Muhammad (1221-1255) : 34 years
10. Imam Muhammad b. Islam Shah (1423-1463) : 40 years
11. Imam Nuruddin Ali (1516-1550) : 34 years
12. Imam Khalilullah I (1550-1585) : 35 years
13. Imam Nizar (1585-1628) : 43 years
14. Imam Sayed Ali (1628-1660) : 32 years
15. Imam Hasan Ali (1660-1694) : 34 years
16. Imam Kassim Ali (1694-1730) : 36 years
17. Imam Khalilullah II (1792-1817) : 25 years

On the other hand, the period of the Imamate of the following Imams lasted for 50 years and above:

1. Imam Mahdi (881-934) : 53 years
2. Imam Mustansir billah I (1036-1095) : 59 years
3. Imam Shamsuddin Muhammad (1257-1310) : 53 years
4. Imam Kassim Shah (1310-1370) : 60 years
5. Imam Islam Shah (1370-1423) : 53 years
6. Imam Abul Hasan Ali (1730-1792) : 62 years
7. Imam Hasan Ali (1817-1881) : 64 years
8. Imam Sultan Muhammad Shah (1885-1957) : 72 years
9. Mawlana Hazar Imam (1957-2007 (cont.) : 50 years

The culture of jubilee commemoration was not prevalent in the societies of Arab and Iran, therefore, no significant celebration in this context is recorded in the historical sources. However, the Takhat Nashini of the Imams was celebrated with great pomp.

It was only destined to the period of Imam Sultan Muhammad Shah to commemorate the Golden Jubilee twice (Bombay and Nairobi), the Diamond Jubilee twice (Bombay and Dar-es- Salaam) and once the Platinum Jubilee (Karachi).