Often times Moses...
Harriet Tubman was often called "Grandma Moses" because she led African-American Slaves to freedom, almost in an analog to the biblical Moses who led Israelite Slaves to freedom.
Tubman was called "Moses" because it refered to a song about how Moses lead his people from slavery to freedom. Slaves often used songs to relay messages while they were working and it was something that the slave holder couldn't understand that there was a message within the song.
"Moses" is what she was called. This is a reference to a Gospel song about how Moses lead his people out of slavery to freedom. This is what Tubman was doing. Often various Gospel songs were used to relay messages among the slaves as they worked and the slave holder had no idea what they were doing.
When individuals became slaves, they lost their freedom, autonomy, and basic human rights. Slaves were considered property and were subject to exploitation, abuse, and mistreatment by their owners. They were often separated from their families and communities, further eroding their sense of identity and belonging.
Slaves owned by Africans were sometimes given more rights, better treatment, and opportunities for integration into society, such as the possibility of marrying into the owner's family or achieving freedom. In comparison, slaves owned by Europeans were often subjected to harsher conditions, faced higher levels of brutality, and had limited chances for social mobility or freedom.
At the command of God (Exodus ch.3), Moses brought the Israelites out of Egyptian slavery (Exodus ch.12), received the Torah from God (Exodus 24:12) and taught it to the Israelites (Deuteronomy 4:5).
Moses' childhood is not described much in the Bible, although popular retellings often cast him as a playmate the Pharaoh with whom he would eventually argue for the freedom of the Hebrews. (In most retellings, this Pharaoh-to-be was Ramses II.)
Slaves attempted to free themselves through methods such as escaping, revolting against their captors, seeking assistance from allies or abolitionists, and participating in underground railroad networks to reach freedom in the North or in Canada. These actions were often dangerous and required great courage, but many slaves were willing to risk their lives for the chance to attain freedom.
Slavery is degrading in and of itself because it deprives people of the basic human right to freedom and degrades them from full humans into property. The practice of slavery is also degrading because often masters were cruel to their slaves and forced them to perform degrading tasks. Often, slaves were seen as sub-human.
Alexander the Great is said to have treated his slaves relatively well compared to the prevailing norms of his time. He often rewarded loyal slaves with freedom and granted them important positions in his administration. However, it is important to remember that slavery was still a harsh and oppressive institution, and while Alexander may have shown some degree of compassion towards his slaves, they ultimately lacked personal freedom and were subject to his authority.
Why should they? The penalties for rebellion were gruesome and harsh. Even though their lives were restricted, most slaves were content to wait until they could buy their freedom or their master manumitted them. Rebellion was simply too big of a risk.