The Quran Verse
Surah 30:4–5;
...And on that day the believers will rejoice in the help of Allah.
Traditional commentators claim Muslims rejoiced at the Roman victory because they preferred the "People of the Book" over the "fire-worshipping" Persians.
Historical critics find this "holy alliance" suspicious. Why would the early Muslims, who were soon to launch a brutal, decades-long war to dismantle the Byzantine Empire, be "rejoicing" in a Byzantine victory?
Many traditions link this "rejoicing" to the Battle of Badr, where Muslims defeated the Meccans. Critics suggest that the verse originally referred to Badr, and the connection to the Romans was a later literary layering used to give the fledgling movement a grand, international prophetic weight.