Final answer:
The Meccans were concerned about the migration of Muslims to Abyssinia due to the possibility of the spread and strengthening of Islam, which could undermine Meccan social and economic power and lead to new alliances or trade networks that challenged Meccan interests.
Step-by-step explanation:
The Meccans were worried about Muslims migrating to Abyssinia for several reasons, but the most significant concern was the potential for the strengthening and spread of Islam, which could challenge the social and economic status quo within Mecca itself. The Christian Kingdom of Aksum (modern-day Ethiopia), under the protection of the Negus, provided a sanctuary for Muslims fleeing persecution. The sheltering of Muslim refugees by the Aksumites represented a form of diplomatic and religious solidarity that the Meccans likely feared could embolden Islam and potentially lead to alliances against Meccan interests. Additionally, it highlighted the potential for Islam to spread beyond the Arabian Peninsula, particularly through pre-existing and burgeoning trade networks, which included the integration of Arab traders with local communities and their subsequent spread of Islamic beliefs.
As Muslims migrated and established trade networks, cultural and religious influences mingled, leading to the spread and establishment of Islamic communities along the East African coast and eventually contributing to the Islamic character of entire regions, including the Swahili coast. Over time, these Islamic communities grew in influence and connections, potentially challenging the Meccans' economic dominance in the region.
Thus, the Meccan concerns about the Muslim migration to Abyssinia were multifaceted, including economic implications, potential political alliances, and the spread of religious influence that threatened their hegemony.