I have been spending the last month or so reading and doing the exercises of Chapters 1-6 of Jech's text, however I noticed a pattern in how Part I is constructed. The way it looks, of the 12 chapters of Part I, the first 6 chapters are on pretty basic set theory that any first course would cover (ZF axioms, ordinals, cardinals, choice, regularity), and the second 6 chapters seem to be applications of these ideas to other fields of mathematics. For instance, a chapter on combinatorics, a chapter on real analysis and measure, a chapter on Boolean algebra, etc. Some of this doesn't fit this pattern, but overall, it seems like chapters 7-12 are pretty skippable for forcing. So I go ahead and start Chapter 13.
Once I turn to Chapter 13, I get lost very quickly. It looks like this part of the text is much more logic-heavy than the other parts were. I have a good understanding of propositional and predicate logic, but no background in model theory or anything else. So my question is as follows:
For those who have Jech's text: are chapters 7-12 really skippable to start forcing? And what is the recommended background in logic to start forcing? Say... chapters 13-15 in Jech.
For those who don't have Jech's text, as I want to make this question more accessible: Forget about the chapter numbers and the specific text. How much logic should I know and review before starting forcing?