What were the concerns of the Abbasid Caliphate when dealing with the Byzantine Empire ?

The Abbasids overthrew the Umayyad dynasty in 750 CE, supporting the mawali, or non-Arab Muslims, by moving the capital to Baghdad in 762 CE.

The Persian bureaucracy slowly replaced the old Arab aristocracy as the Abbasids established the new positions of vizier and emir to delegate their central authority.

The Abbasids maintained an unbroken line of caliphs for over three centuries, consolidating Islamic rule and cultivating great intellectual and cultural developments in the Middle East in the Golden Age of Islam.

The Fatimid dynasty broke from the Abbasids in 909 and created separate line of caliphs in Morocco, Algeria, Tunisia, Libya, Egypt, and Palestine until 1171 CE.

Abbasid control eventually disintegrated, and the edges of the empire declared local autonomy.

Though lacking in political power, the dynasty continued to claim authority in religious matters until after the Ottoman conquest of Egypt in 1517.

i believe its the indians