Those who owed Muhammad's teachings became known as
meaning those who surrender to God

Muslims.

Explanation:

Islam is a religion, and the people who take part in the religion are called muslims.

Not all arab people owed Muhammad's teachings became known as

meaning those who surrender to God

Sharia is a specific type of islam.

Muslims is the right answer I think.

Hope this helps:)

The event that made the great schism forever permanent was the  fourth crusade when venetain army captured constantinople but it didn; t created permanent schism but led to distrust but for a long time the deepering schism took place when center of eatsern orthdox faith became moscow