Religious significance of Spirituals
Negro spirituals were primarily expressions of religious faith. Some may also have served as socio-political protests veiled as assimilation to white American culture. They originated among enslaved Africans in the United States. Slavery was introduced to the British colonies in the early 17th century, and enslaved people largely replaced indentured servants as an economic labor force during the 17th century. These people would remain in bondage for the entire 18th century and much of the 19th century. Most were not fully emancipated until the ratification of the Thirteenth Amendment to the United States Constitution.

Suppression of indigenous religion
During slavery in the United States, there were systematic efforts to de-Africanize the captive Black workforce. Enslaved people were forbidden from speaking their native languages.

Because they were unable to express themselves freely in ways that were spiritually meaningful to them, enslaved Africans often held secret religious services. During these “bush meetings,” worshippers were free to engage in African religious rituals such as spiritual possession, speaking in tongues and shuffling in counterclockwise ring shouts to communal shouts and chants. It was there also that enslaved Africans further crafted the impromptu musical expression of field songs into the so-called "line singing" and intricate, multi-part harmonies of struggle and overcoming, faith, forbearance and hope that have come to be known as Negro spirituals.

Restrictions were placed on the religious expression of slaves. Rows of benches in places of worship discouraged congregants from spontaneously jumping to their feet and dancing. The use of musical instruments of any kind often was forbidden, and slaves were ordered to desist from the "paganism" of the practice of spiritual possession.

Replacement with Christianity
Nonetheless, the Christian principles which teach that those who suffer on earth hold a special place with God in heaven undoubtedly spoke to the enslaved, who saw this as hope and could certainly relate to the suffering of Jesus. For this reason many slaves genuinely embraced Christianity.

While slaveowners used Christianity to teach enslaved Africans to be long-suffering, forgiving and obedient to their masters, as practiced by the enslaved, it became something of a liberation theology. The story of Moses and The Exodus of the "children of Israel" crossing the Jordan River, and the idea of an Old Testament God who struck down the enemies of His "chosen people" resonated deeply with the enslaved ("He's a battleaxe in time of war and a shelter in a time of storm"). The lyrics of Christian spirituals reference symbolic aspects of Biblical images such as these, in songs like Michael Row the Boat Ashore. In Black hands and hearts, Christian theology became an instrument of liberation.

Claims of coded messages
Many internet sources and popular books claim that songs such as “Wade in the Water” contained explicit instructions to fugitive slaves on how to avoid capture, and on which routes to take to successfully make their way to freedom.^[9] This particular song allegedly recommends leaving dry land and taking to the water as a strategy to throw pursuing bloodhounds off one's trail. “The Gospel Train” and “Swing Low, Sweet Chariot” are equally supposed to contain veiled references to the Underground Railroad, and many sources assert that Follow the Drinking Gourd contained a coded map to the Underground Railroad.