What made judaism appealing to followers?

I believe it because they give people a sense of belonging to a certain community.
Rather than tied solely to religious aspects, Judaism followers treated each other like they're belonged to a close family (they are taught a similar culture, way of life, way to behave, etc.)
This type of sense belonging was really powerful since humans are naturally created to work as a group rather than following individualistic pattern.

He gathered information from primary sources.