Mr Sewall was refereing to a biblical scenario, The one of Joseph, to talk about how slavery should not be considered whatsoever. He refered to three major arguments to defend his abolitional document: African slaves were descended from Adam and Eve, Israelites were expressly forbidden from buying and selling slaves and The enslave,net of Joseph was illegal and immoral. Based on this document, Sewall appealed to christians by leading them to the immediate emancipation of countless slaves.
this is the best i can do hope it helps
Think about what the story is mainly about and what's its really focusing on that's how you get the purpose of why the author included that sentence
