Peter, I believe your initial question was is there or was there a tradition among African Americans of changing our names upon being baptized. My answer to that question is that I don't believe that choosing or being given a new name when you are baptized is now or has ever been a tradition in African American Baptist denomination congregations or in any other African American Christian congregations.

I understand from your latest post that you were informed that this is a tradition in the Eastern Orthodox Church. I also would be interested to know if this name changing tradition is practiced among any (other) Christian denominations, particularly in the USA.

With regards to understanding the reasons for the lyrics of the spiritual "If He Change My Name", it might be helpful to consider this information about Black slavery in the USA:

Among other beneficial results of the end of chattel slavery in the USA was that Black Americans had the right to name their children rather than having them be named by others (meaning their children's owner/s).

During the three centuries of slavery in the United States, some enslaved Black people had chosen names for their children without any intervention of their slave owners. A considerable proportion of those names were chosen or created using their own naming traditions. Those naming traditions were very much influenced by West African and Central African practices. But the owners of those slaves, if they chose, could disregard the will and the desire of a child's parents and name that child himself or herself. Even then, the child might have a "basket" name (a name that their parent or parents called them when they were away from the slave owners).

Contrary to commonly held beliefs, some enslaved Black Americans had last names and these last names were not necessarily the names of their current owners. However, if those slaves had a last name that they used, their present owner could and often did choose to disregard that surname. But a considerable number of enslaved Black people in the United States had no surnames. Of course, one shouldn't forget that there were also free Black people in the South and elsewhere who had last names. However, this brief overview focuses on the naming practices of enslaved Black people-particularly in the 19th century USA South-and not Black people during that time who were born free or who were freed.

At the end of the US Civil War one of the most immediate decisions that many newly freed Black Americans had to make was which last name they would use. Black people called last names "entitles", a term which implies that they knew that they were "entitled" by the status of citizens to have a last name. Some Black Americans who previously hadn't had a last name chose chose a last name. Also contrary to common belief, many of these newly freed people didn't chose the last name of their enslavers. Instead, those people choose another last name. In one family reunion that I attended as a guest/ performer, the Black family tells how two brothers out of three walked to a plantation of a man who was "respected" because he was fair in the way he treated his slaves. These two brothers asked permission of that plantation owner to use his name. The man gave his permission, and both brothers claimed that name, but overtime or when it was written down by whoever recorded those names, that surname came to be spelled differently. There is another story that I read about a family whose last name is "Beman" because their great great grandfather who was newly freed wanted people to know that he was a man (and not an animal as many people in those days considered Black people to be). There are many such stories of how African Americans got their new last names. My point is that one shouldn't underestimate the importance of names for Black Americans.

As the lyrics to the song "If He Change My Name" indicates, a person's new circumstances (as a born again Christian) confers upon him or her new responsibilities (the person is supposed to follow God's Word and adhere to the church's rules). Those lyrics also indicate that being born again (which is symbolized by the phrase "having a new name" means that the person may be challenged by people in the world (be tempted by them to go back to worldly, sinful ways.

As to why the words the "If He Change My Name" are allegorical instead of directly saying "I told Jesus it would be alright if I have to take on new responsibilities and if I am confronted with worldly challenges because I decided to become a Christian, to use
hip-hop language, "that's the way we roll" (meaning that's how we do things). In other words, that indirect way of speaking is a characteristic of African American music style.