The connector "thus" could be read as connecting this verse to the previous verse, or as an introduction to a separate sentiment. If it stands alone, then he is simply adding another teaching. If it connects to the previous verse, then the teaching that "every man should love his neighbor as himself" should be a summary of the previous text.
While it is not clearly a summary of the dangers of godless teachers, it does tie up the argument with another plea for social unity rather than social stratification, which Alma used to begin his discussion. It may be that loving one's neighbor was seen as the antithesis to social stratification, which led to seeing oneself as better or worse than ones neighbor (see verse 7 "Ye shall not esteem one flesh above another, or one man shall not think himself above another").