During the reign of Khosrow Parviz there was a war between Iran and Rome which continued for 24 years, from 604 to 628 A.D. In the seventh year of our prophet's emigration, about 616 A.D., two of the Persian Commanders named SHÄHIN and SHAHRBRÄZ attacked the Dominion of Eastern Roman Empire (BYZANTINE), and vanquished the Roman Emperor. In that fight the Romans who were Christians lost Jerusalem to Persians, and in the sight of the world Christianity was despised by Iranians who were thought to have been Dualists.

      The Pagan Quraish who took the affirmative side of Persians and sympathized them, rejoiced at the overthrow of Rome by Persians and increased their taunt, and jeered at Moslems whose Message was a reviewal of the Message of Jesus, preached in Jerusalem.

      Then to this effect, the above passage was revealed that clearly foretold the next defeat, which afflicted Persians. The heathens of Mecca laid a heavy wager against the fulfilment of the prophecy with ABUBEKR, the later first Khalif of Islam, and they lost it, when the prediction came to pass. It actually so happened at the Battle of ISSUS in 622ِ4, when HERACLIUS of Rome carried his campaign in the heart of Persian Kingdom. This happened when the idolaters of Mecca were vanquished at their fight with muslims in the Battle of Badr, and believers rejoiced for a twofold victory:-

      ``....And on that day believers will rejoice.''

      So when the twofold promise of God was fulfilled, Moslems had a twofold rejoice.