Judaism as a model religion
Spinoza's argument is a response to a certain kind of Christian that was dominating the cultural discourse during Spinoza's day. Namely, Spinoza hates those people who accomplish social power and dominion by accepting religious ideas they don't really believe. He says that the Jewish has been continued by these kind of people, and Christianity too, but since Christianity uses Judaism as a model religion (in that it was Jesus's own religion), Spinoza lets Judaism represent religion. That makes a narrow argument, though, because his arguments don't translate to religions like Daoism or Buddhism, or even really to Christian mysticism.
The motif of power
Spinoza views the Bible, its traditions, the religious people of his own community, and the effect of religion itself, all through the lens of power. His opinion is that people are religious because that is an expedient way to become powerful, and to gain authority in one's community, but ultimately, the accidental damage that is done to Philosophy is that people think religion is more authoritative than their own common sense. By playing the religious game for power, Spinoza feels that people slowly forget the objective truth of their own literal reality.
The motif of comfort and laziness
Spinoza knows from experience that it is hard work to think for one's self, especially during a time like Spinoza's when anti-religious language was not tolerated at the social level. When he criticizes the religious people he knows, Spinoza feels it is for safety, comfort, and sloth that religious people stop thinking for themselves.
Religion as a lens
By allowing religion or the Bible into a position of authority, Spinoza feels that the readers would actually damage their own relationship to reality and to the Bible itself. Because hyper-religious people have agreed to nonsensical religious opinions without the philosophical or scientific evidence to support their believes, he feels their opinions of reality are predicated on fantasy.
The motif of human fear and shame
A lot of readers have heard that Spinoza is an angry person, but he is a writer with a passionate rebuttal to a horrifying problem that many in his day would not even acknowledge—that religion infected his community with shame and fear that led to power-struggles and paranoia, and in those situations, he feels the religion has done more harm than good. He feels humans should not allow delusional shame to be a part of their philosophy about the world.
