After a little research, I have seen a lot of Muslim critic targeting this hadith as a reference to Islam being racist. The hadith is as follows:
Jabir (Allah be pleased with him) reported: There came a slave and pledg- ed allegiance to Allah's Apostle ﷺ on migration; he (the Holy Prophet) did not know that he was a slave. Then there came his master and demanded him back, whereupon Allah's Apostle ﷺ said: Sell him to me. And he bought him for two black slaves, and he did not afterwards take allegiance from anyone until he had asked him whether he was a slave (or a free man)
An argument of such a critic is "Muhammad not only trades in slaves, but he deems the life of one slave pledging himself to Islam as MORE worthy than two African non-converts."
What would be a general response to such an argument? As a matter of fact, an explanation of this hadith would be appreciated.
As an attempt to answering my own question, I was thinking of this:
So, by default our prophet has already made it clear in the last sermon that a white isn't superior to a black nor is a non-Arab superior to an Arab or vice versa. So when our prophet decided to sell 2 black individuals for an individual who has pledged allegiance to the prophet, it wasn't because of race or that the black slaves were expendable but maybe for a certain reason where assuming the 2 black slaves were more valued to the slave master, than anything such as money or animal. It's also possible that the slave who pledged allegiance to our prophet could have been black. Hence bought him for 2 black non-muslims.
At this point, I am only rationalizing on certain possibilities but not really getting anywhere. I just hope someone can have a better explanation than myself with proper evidence.