Qur'anic verses - Romans versus Persians:

The Pagans rejoiced at the overthrow of Rome by Persia. All believers, the people of the Book including the followers of the new religion 'the Islam' were saddened by this remarkable defeat of the Christian Empire. The Roman Empire under Heraclius lost most of its Asiatic territory and was hemmed in on all sides at its capital, Constantinople. Further to this defeat, and after the revelation of these Qur'anic verses, Jerusalem was lost in 614/5 AD., the Christians were massacred and the churches were burnt. The Pagans of Makkah, the birth place of Muhammad, rejoiced the victory of Persia under their king, Chosroes II, and challenged Muhammad and his followers if the Roman Empire could ever overcome this defeat as God promised in these Qur'anic verses. The promise of God of future victory was in fact for all believers to share rejoice and was restricted in time as well; the word few here is referred to the number 3-9 in Arabic language. Within this span of time, the Persians were taken by surprise and routed in 622. Heraclius fought a decisive battle with the Persians at Issus, in the same plain in which Alexander the Great had defeated the Persians of his day in his famous march to Syria and Egypt.

This victory was coupled with the Muslims' first victory against the unbelievers of Makkah in Badr in 624. God is able to carry out His Plan in full, and there is no power that can stop or delay His Plan.